Is displacement a vector quantity?

State whether distance is a scalar or a vector quantity.

Change the speed of 6 m/s into km/h.

What name is given to the speed in a specified direction?

Give two examples of bodies having non-uniform motion.

Name the physical quantity obtained by dividing ‘Distance travelled’ by ‘Time Taken’ to travel that distance.

What do the following measure in a car?

(a) Speedometer (b) Odometer

Name the physical quantity which gives us an idea of how slow or fast a body is moving.

Under what conditions can a body travel a certain distance and yet its resultant displacement by zero?

In addition to speed, what else should we know to predict the position of a moving body?

When is a body said to have uniform velocity?

Under which condition is the magnitude of average velocity equal to average speed?

Which of the two can be zero under certain conditions: average speed of a moving body or average velocity of a moving body?

Give one example of a situation in which a body has a certain average speed but its average velocity is zero.

What is the acceleration of a body moving with uniform velocity?

What is the other name of negative acceleration?

Name the physical quantity whose SI unit is :

(a) m/s (b) ms/²

What type of motion is exhibited by a freely falling body?

What is the SI unit of retardation?

Fill in the following blanks with suitable words:

(a) _______ is a vector quantity whereas ________is a scalar quantity.

(b) The physical quantity which gives both, the ___ and _____ of motion of a body is called its velocity.

(c) A motorcycle has a steady acceleration Of 3 m/s². This means that every second its ………increases by ………… .

(d) ___________ is the rate of change of displacement. It is measured in m/s.

(e) ____________ is the rate of change of velocity . It is measured in ………………… .

What type of motion, uniform or non-uniform, is exhibited by a freely falling body? Give reason for your

State whether speed is a scalar or a vector quantity. Give reason for your choice.

Bus X travels a distance of 360 km is 6 hours. Whereas bus Y travels a distance of 427 km in 7 hours. Which bus travels faster?

Arrange the following speeds in increasing order (keeping the least speed first) :

(i) An athlete running with a speed of 20 m/s.

(ii) A bicycle moving with a speed of 400 m/min.

(iii) A scooter moving with a speed of 60 km/h.

Write the formula for acceleration. Give the meaning of each symbol which occurs in it.

A train starting from railway Station attains a speed of 30 m/s in one minute. Find its acceleration.

What term is used to denote the change of velocity with time?

Give one word which means the same as ‘moving with a negative acceleration”.

The displacement of a moving object in a given interval of time is zero. Would the distance travelled by the object also be zero? Give reason for your Answer

A snail covers a distance of 1000 metres in 550 hours. Calculate the average speed of snail in km/h.

A tortoise moves a distance of 1000 metres in 15 mintues. What is the average speed of tortoise in km/h?

If a sprinter runs a distance of 1000 metres in 9.83 seconds, calculate his average speed in km/h

A motorcyclist drives from place A to B with a uniform speed of 60 km h^-1 and returns from place B to A with a uniform speed of 40 km h^-1. Find his average speed.

A motorcyclist starts from rest and reaches a speed of 12 m/s after travelling with uniform acceleration for 6 s. What is his acceleration?

An aircraft traveling at 800 km/h accelerates steadily at 10 km/h per second. Taking the speed of sound as 1100 km/h at the aircraft’s altitude, how long will it take to reach the ‘sound barrier’?

If a bus travelling at 40 m/s is subjected to a steady deceleration of 5 m/s², how long will it take to come to rest?

What is the difference between ‘distance travelled’ by a body and its ‘displacement’? Explain with the help of a diagram.

An ant travels a distance of 3 cm from P to Q and then moves a distance of 4 cm at right angles to PQ. Find its resultant displacement.

Define motion. What do you understand by the terms ‘uniform motion’? Explain with examples.

Define speed. What is the SI unit of speed?

What is meant by (i) average speed, and (ii) uniform speed?

Define velocity. What is the SI unit of velocity?

What is the difference between speed and velocity?

Convert a speed of 90 km/h into m/s.

What is meant by the term ‘acceleration’? State the SI unit of acceleration.

Define the term ‘uniform acceleration’. Give one example of a uniformly accelerated motion.

The distance between Delhi and Agra is 400 km. A train travels the first 200 km at a speed of 100 km/h. How fast must the train travel the next 200 km, so as to average 140 km/h for the whole journey?

A train travels the first 20 km at a uniform speed of 40 km/h; the next 75 km at a uniform speed of 50 km/h; and the last 10 km at a uniform speed of 20 km/h. Calculate the average speed for the entire train journey.

A car is moving along a straight road at a steady speed. It travels 200 m in 5 seconds :

(a) What is its average speed?

(b) How far does it travel in 1 second?

(c) How far does it travel in 6 seconds?

(d) How long does it take to travel 240 m?

A particle is moving in a circular path of radius r. The displacement after a circle would be:

A. 0

B. pr

C. 2r

D. 2pr

The numerical ratio of displacement to distance for a moving object is :

A. < 1

B. = 1 or > 1

C. > 1

D. = 1 or < 1

A boy is sitting on a merry-go-round which is moving with a constant speed of 20 ms^-1. This means that the boy is :

A. at rest

B. moving with no acceleration

C. in accelerated motion

D. moving with uniform velocity

In which of the following cases of motion, the distance moved and the magnitude of displacement are equal?

A. if the car is moving on straight road

B. if the car is moving on circular road

C. if the pendulum is moving to and fro

D. if a planet is moving around the sun

The speed of a moving object is determined to be 0.12 m/s. This speed is equal to :

A. 2.16 km/h

B. 1.08 km/h

C. 0.432 km/h

D. 0.0216 km/h

A freely falling object travels 4.9 m in 1^st second, 14.7 m in 2^nd second, 24.5 m in 3^rd second, and so on. This data shows that the motion of a freely falling object is a case of:

A. uniform motion

B. uniform acceleration

C. no acceleration

D. uniform velocity

When a car runs on a circular track with a uniform speed, its velocity is said to be changing. This is because:

A. the car has a uniform acceleration

B. the directions of car varies continuously.

C. the car travels unequal distances in equal time intervals

D. the car travels equal distances in unequal time intervals

Which of the following statement is correct regarding velocity and speed of a moving body?

A. velocity of a moving body is always higher than its speed

B. speed of a moving body is always higher than its velocity

C. speed of a moving body is its velocity in a given direction

D. velocity of a moving body is its speed in a given direction.

Which of the following can sometimes be ‘zero’ for a moving body?

(i) average velocity

(ii) distance travelled

(iii) average speed

(iv) displacement

A. only (i) B. (i) and (ii)

C. (i) and (iv) D. only (iv)

When a car driver travelling at a speed of 20 m/s applies brakes and brings the car to rest in 40 s, then retardation will be :

A. + 2 m/s²

B. -2 m/s²

C. - 0.5 m/s²

D. + 0.5 m/s²

Which of the following could not be a unit of speed?

A. km/h B. s/m

C. m/s D. mm s^-1

One of the following is not a vector quantity. This one is :

A. displacement B. speed

C. acceleration D. velocity

Which of the following could not be a unit of acceleration?

A. km/s²

B. cm s²

C. km/s

D. m/ s²

A body is moving along a circular path of a radius R. What will be the distance travelled and displacement of the body when it completes a revolution?

If on a round trip you travel 12 km and then arrive back home:

(a) What distance have you travelled?

(b) What is your final displacement?

A body travels a distance of 6 km towards East, then 4 km towards North and finally 9 km towards west.

(i) What is the total distance travelled?

(ii) What is the resultant displacement?

A boy walks from his classroom to the bookshop along a straight corridor towards North. He covers a distance of 40 m in 50 seconds to reach the bookshop. After buying a book, he travels the same distance in the same time to reach back in the classroom. Find (a) average speed, and (b) average velocity, of the boy

A car travels 100 km at a speed of 90 km/h and returns with a speed of 30 km/h. Calculate the average speed for the whole journey.

A ball hits a wall horizontally at 8.0 m/s^-1. It rebounds horizontally at 4.4 m s^-1. The ball is in contact with the wall for 0.040 s. What is the acceleration of the ball?

What remain constant in uniform curcular motion?

What change continuously in uniform circular motion?

State whether the following statement is true of false:

Earth moves round the sun with non- uniform velocity.

A body goes round the sun with constant speed in a circular orbit. Is the motion uniform or accelerated?

What conclusion can you draw about the velocity of a body from the displacement-time graph shown below :

Name the quantity which is measured by the area occupied under the velocity-time graph.

What does the slope of a speed-time graph indicate?

What does the slope of a distance-time graph indicate?

Give one example of a motion where an object does not change its speed but its direction of motion changes continuously.

Name the type of motion in which a body has a constant speed but not constant velocity.

What can you say about the motion of a body if its speed-time is a straight line parallel to the time axis?

What conclusion can you draw about the speed of a body from the following distance-time graph:

What can you say about the motion of a body whose distance time graph is a straight line parallel to the time axis?

What conclusion can you draw about the acceleration of a body from the speed time graph shown below?

A satellite goes round the earth in a circular orbit with constant speed. Is the motion uniform or accelerated?

What type off motion is represented by the tip of ‘seconds’ hand’ of watch? Is it uniform or accelerated?

Fill in the following blanks with suitable words :

(a) If a body moves with ___________, its acceleration is zero

(b) The ___ of a distance time graph indicates speed of a moving body.

(c) The slope of a ______graph of a moving body gives its acceleration

(d) In a speed-time graph, the area enclosed by the speed-time curve and the time axis gives the ………………by the body.

(e) It is possible for something to accelerate but not change its speed if it moves in a ……………

Is the uniform circular motion accelerated? Give reasons for your Answer.

Write the formula to calculate the speed of a body moving along a circular path. Give the meaning of each symbol which occurs in it.

Explain why, the motion of a body which is moving with constant speed in a circular speed in a circular path is said to be accelerated.

What is the difference between uniform linear motion and uniform circular motion? Explain with examples.

State an important characteristic of uniform circular motion. Name the force which brings about uniform circular motion.

Find the initial velocity of a car which is stopped in 10 seconds by applying brakes. The retardation due to brakes is 2.5 m/s².

Describe the motion of a body which is accelerating at a constant rate of 10 ms². Calculate the speed of the motorcycle after 10 seconds, and the distance travelled in this time.

A motorcycle moving with a speed of 5 m/s is subjected to an acceleration of 0.2 m/s². Calculate the speed of the motorcycle after 10 seconds, and the distance travelled in this time.

A bus running at a speed of 18 km/h is stopped in 2.5 seconds by applying brakes. Calculate the retardation produced.

A train starting from rest moves with a uniform acceleration of 0.2 m/s² for 5 minutes. Calculate the speed acquired and the distance travelled in this time.

Name the two quantities, the slope of whose graph gives :

(a) speed, and (b) acceleration

A cheetah starts from rest, and accelerates at 2 m/s² for 10 seconds. Calculate :

(a) the final velocity

(b) the distance travelled.

A train travelling at 20 m s^-1 accelerates at 0.5 m s^-2 for 30 s. How far will it travel in this time?

A cyclist is travelling at 15 m s^-1. She applies brakes so that she does not collide with a wall 18 m away. What deceleration must she have?

Draw a velocity-time graph to show the following motion :

A car accelerates uniformly from rest for 5 s; then it travels at a steady velocity for 5 s.

The velocity-time graph for part of a train journey is a horizontal straight line. What does this tell you about

(a) the train’s velocity, and

(b) about its acceleration?

Explain the meaning of the following equation of motion :

v = u + at

where symbols have their usual meanings.

A body starting from rest travels with uniform acceleration. If it travels 100 m in 5 s, what is the value of acceleration?

Derive the formula : v = u + at; where

the symbols have usual meanings.

A bus was moving with a speed of 54 km/h. On applying brakes it stopped in 8 seconds. Calculate the acceleration.

Derive the formula: ,where the symbols have usual meanings.

A train starting from stationary position and moving with uniform acceleration attains a speed of 36 km per hour in 10 minutes. Find its acceleration.

Write the three equations of uniformly accelerated motion. Give the meaning of each symbol which occurs in them.

A car acquires a velocity of 73 km per hour in 10 seconds starting from rest. Find (i) the acceleration, (ii) the average velocity, and (iii) the distance travelled in this time.

What is meant by uniform circular motion? Give two examples of uniform circular motion.

The tip of seconds’ hand of a clock takes 60 seconds to move once on the circular dial of the clock. If the radius of the dial of the clock be 10.5 cm, calculate the speed of the tip of the seconds’ hand of the clock (given p=)

Show by means of graphical method that :

v = u + at where the symbols have their usual meanings.

Show by using the graphical method that : s = ut + at², where the symbols have usual meanings.

Derive the following equation of motion by the graphical method : v² = u² + 2as, where the symbols have their usual meanings.

A bus increases its speed from 36 km/h to 72 km/h in 10 seconds. Its acceleration is :

A. 5 m/s²

B. 2 m/s²

C. 3.6 m/s²

D. 1 m/s²

A bus moving along a straight line at 20 m/s undergoes an acceleration of 4 m/s². After 2 seconds, its speed wil be :

A. 8 m/s B. 12 m/s

C. 16 m/s D. 28 m/s

The slope of a speed-time graph gives :

A. distance travelled

B. velocity

C. acceleration

D. displacement

The area under a speed-time graph represents a physical quantity which has the unit of :

A. m

B. m²

C. m s^-1

D. m s^-2

If the displacement of an object is proportional to the square of time, then the object is moving with :

A. uniform velocity

B. uniform acceleration

C. increasing acceleration

D. decreasing acceleration

Answer||B

Four cars A, B, C and D are moving on a levelled, straight road. Their distance-time graphs are shown in the given figure. Which of the following is the correct statement regarding the motion of these cars?

A. car A is faster than car D

B. car B is the slowest

C. car D is faster than the car C

D. car C is the slowest

A car of mass 1000 kg is moving with a velocity of 10 m s^-1. If the velocity-time graph for this car is a horizontal line parallel to the time axis, then the velocity of car at the end of 25 s will be :

A. 25 m/s^-1 B. 40 m/s^-1

C. 10 m/s^-1 D. 250 m/s^-1

A car moving with an initial velocity of 10 m/s slows down at a constant deceleration and stops after traveling 400 m. What is the time (in seconds) taken by the car to come to a stop?

A. 80 sec B. 60 sec

C. 25 sec D. 40 sec

A sprinter is running along the circumstance of a big sports stadium with constant speed. Which of the following do you think is changing in this case?

A. magnitude in which the sprinter being produced

B. distance covered by the sprinter per second

C. direction in which the sprinter is running

D. centripetal force acting on the sprinter.

A student draws a distance-time graph for a moving object shown here, the part which indicates uniform deceleration of the object is :

A. ST B. QR

C. RS D. PQ

A student draws a distance-time graph for a moving scooter and finds that a section of the graph is a horizontal line parallel to the time axis. Which of the following conclusion is correct about this section of the graph?

A. the scooter has uniform speed in this section

B. the distance travelled by scooter is the maximum in this section

C. the distance travelled by the scooter is the minimum in this section

D. the distance travelled by the scooter is zero in this section

Which one of the following is most likely not a case of uniform circular motion?

A. motion of the earth around the sun

B. motion of a toy train on a circular track

C. motion of a racing car on a circular track

D. motion of hours’ hand on the dial of a clock

Fig 8.11 shows the distance-time graph of three objects A,B and C. Study the graph and answer the following questions:

(a) Which of the three is travelling the fastest?

(b) Are all three ever at the same point on the road?

(c) How far has C travelled when B passes A?

(d) How far has B travelled by the time it passes C?

The speed-time graph for a car is shown is Fig. 8.12.

(a) Find how far does the car travel in the first 4 seconds. Shade the area on the graph that represents the distance travelled by the car during the period.

(b) Which part of the graph represents uniform motion of the car?

A body with an initial velocity x moves with a uniform acceleration y. Plot its velocity-time graph is a straight line?

Given alongside is the velocity-time graph for a moving body :

Find (i) Velocity of the body at point C.

(ii) Acceleration acting on the body between A and B.

(iii) Acceleration acting on the body beyween B and C.

A body is moving uniformly in a straight line with a velocity of 5 m/s. Find graphically the distance covered by it in 5 seconds.

The speed-time graph of an ascending passenger lift is given alongside.

What is the acceleration of the lift :

(i) During the first two seconds?

(ii) between second and tenth second?

(iii) during the last two seconds?

A car is moving on a straight road with uniform acceleration. The speed of the car varies with time as follows :

Draw the speed-time graph by chooding a convenient scale. From this graph :

(i) Calculate the acceleration of the car.

(ii) Calculate the distance travelled by the car in 10 seconds.

The graph given alongside shows how the speed of a car changes with time :

(i) What is the initial speed of the car?

(ii) What is the maximum speed attained by the car?

(iii) Which part of the graph shows zero acceleration?

(iv) Which part of the graph shows varying retardation?

(v) Find the distance travelled in first 8 hours.

Three speed-time graphs are given below :

Which graph represents the case of :

(i) a cricket ball thrown vertically upwards and returning to the hands of the thrower?

(ii) a trolley decelerating to a constant speed and then accelerating uniformly?

Study the speed-time graph of a car given alongside and answer the following questions :

(i) What type of motion is represented by OA?

(ii) What type of motion is represented by AB?

(iii) Wht type of motion is represented by BC?

(iv) What is the acceleration of car from O to A?

(v) What is the acceleration of car A to B?

(vi) What is the retardation of car from B to C?

What type of motion is represented by each one of the following graphs?

A car is travelling along the road at 8 m s^-1. It accelerates at 1 m s^-2. For a distance of 18 m. How fast is it then travelling?

A car is travelling at 20 m/s along a road. A child runs out into the road 50 m ahead and the car driver steps on the brake pedal. What must the car’s deceleration be if the car is to stop just before it reaches the child?