Introduction to Equations of Motion

Q.

The brakes applied to a car produce a negative acceleration of 6 $m/s^2$. If the car takes 2 seconds to stop after applying the brakes, calculate the distance it travels during this time. (Give your answer in m)

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Q.

A car moving with a speed of $40km{h}^{-1}$ can be stopped by applying brakes after at least $2m$. If the same car is moving with a speed of $80km{h}^{-1}$., what is the minimum stopping distance

1. $8m$

2. $2$$m$

3. $4m$

4. $6m$

Q. A driver of a car travelling at $52km{h}^{-1}$ applies the brakes and accelerates uniformly in the opposite direction. The car stops in $5s$. Another driver travelling at $3km{h}^{-1}$ in another car applies his brakes slowly and stops in $10s$. On the same graph, plot the speed vs. time graphs for the two cars. Which of the two cars travelled farther after the brakes were applied?
[3 Marks]

Q.

A car moving at speed $50km/h$ one applying brake stops at a distance of $6m$. If same car move with the velocity $100km/h$, what distance it cover after applying the brakes.

1. $12m$

2. $18m$

3. $24m$

4. $6m$

Q.

Brakes are applied by a truck to produce retardation of $10m{s}^{-2}$. If the truck takes 5 seconds to stop after applying the brakes, the distance covered by the truck before coming to rest is

1. 125 m

2. 150 m

3. 175 m

4. 200 m

Q. Why does a gun recoil when a bullet is fired ? Explain recoil? (2 marks)

Q.

Brakes are applied to a truck to produce an acceleration of $–10m/s^2$. If the truck takes $5s$ to stop after applying the brakes, the distance covered by the truck before coming to rest is $250m$.

1. 200 m

2. 125 m

Q.

Brakes are applied to a truck to produce an acceleration of $–10m/s^2$​. If the truck takes $5s$ to stop after applying the brakes, the distance covered by the truck before coming to rest is $250m$.

1. 200 m

2. 125 m

Q.

Brakes are applied to a truck to produce an acceleration of $–10m{s}^{-2}$​. If the truck takes $5s$ to stop after applying the brakes, then find the distance covered by the truck before coming to rest.

1. $250m$
2. $125m$
3. $-125m$
4. $-250m$

Q. Two scooters starting from rest accelerate uniformly at the same rate. Time taken by second scooter to travel is twice the time taken by the first scooter. Then the relation between the distance covered by the first scooter $\left(S_1\right)$ to that of the second scooter $\left(S_2\right)$ is

1. $S_1=S_2$
2. $S_1=2S_2$
3. $S_2=3S_1$
4. $S_2=4S_1$

Q. An aeroplane accelerates from rest down a runaway at $3m{s}^{-2}$ for $30s$ until it finally lifts off the ground. Determine the distance travelled before take off.

1. $1350m$
2. $1620m$
3. $1482m$
4. $1700m$

Q. A truck and a car are moving on a smooth, level road such that the K.E. associated with them is same. Brakes are applied to both of them simultaneously. Which one will cover a greater distance before it stops ?

1. Car
2. Truck
3. Both will cover the same distance
4. Nothing can be decided

Q.

Brakes are applied to a truck to produce an acceleration of $–10m{s}^{-2}$​. If the truck takes $5s$ to stop after applying the brakes, then find the distance covered by the truck before coming to rest.

1. $250m$
2. $125m$
3. $-125m$
4. $-250m$

Q.

If the displacement of a body is in direct proportion to the square of the time lapsed, then the acceleration is

1. Increasing

2. Constant

3. Decreasing

4. Can't say

Q. An aeroplane accelerates from rest down a runaway at $3m{s}^{-2}$ for $30s$ until it finally lifts off the ground. Determine the distance travelled before take off.

1. $1350m$
2. $1620m$
3. $1700m$
4. $1482m$

Q. Two scooters starting from rest accelerate uniformly at the same rate. Time taken by second scooter to travel is twice the time taken by the first scooter. Then the relation between the distance covered by the first scooter $\left(S_1\right)$ to that of the second scooter $\left(S_2\right)$ is

1. $S_1=S_2$
2. $S_1=2S_2$
3. $S_2=3S_1$
4. $S_2=4S_1$

Q. Two scooters starting from rest accelerate uniformly at the same rate. Time taken by second scooter to travel is twice the time taken by the first scooter. Then the relation between the distance covered by the first scooter $\left(S_1\right)$ to that of the second scooter $\left(S_2\right)$ is

1. $S_1=S_2$
2. $S_1=2S_2$
3. $S_2=3S_1$
4. $S_2=4S_1$

Q.

Brakes are applied to a truck to produce an acceleration of $–10m{s}^{-2}$​. If the truck takes $5s$ to stop after applying the brakes, then find the distance covered by the truck before coming to rest.

1. $250m$
2. $125m$
3. $-125m$
4. $-250m$

Q. A car moving with initial velocity of $15m{s}^{-1}$ accelerates at the rate of $4m{s}^{-2}$. What is the final velocity of the car after $10s$?

1. $55m{s}^{-1}$
2. $65m{s}^{-1}$
3. $40m{s}^{-1}$
4. $70m{s}^{-1}$

Q. What would happen to a car traveling west at a constant velocity of 55 MPH without any influence of external force?

1. The car would continue moving west with a velocity of 55 MPH
2. The car would increase its velocity without changing acceleration
3. The car would slow down but never reach 0 velocity
4. The car would slow down and come to rest
5. The car would slowly increase its velocity approaching but not reaching the speed of light