J J Science Academy
1. A particle starts moving along a straight line with velocity ' $(u)$ ' and a constant acceleration ' $(a)$ '. After time ' $(t)$ ', it acquires velocity ' $(v)$ '. Then the average velocity in time $(t)$ is
2. A car accelerates from rest at a constant rate $(\alpha)$ for some time, after which it decelerates at a constant rate $(\beta)$ and comes to rest. If the total time elapsed is $(t)$, then the maximum velocity acquired by the car is
3. A body moving along negative X -axis, with speed $(u)$, is subjected to unit acceleration along positive X -axis, when it is at the origin. The time it takes to return to origin is
4. A body moving along negative X -axis, with speed $(u)$, is subjected to unit acceleration along positive $(X-axis)$, when it is at the origin, the distance it travels before reaching origin is
5. A particle experiences, constant acceleration for 20 second after starting from rest. If it travels a distance $(S_1)$ in the first 10 second and a distance $(S_2)$ the next 10 second, then
6. Tripling the speed of a motor car, multiplies the distance needed for stopping it by
7. A body is accelerated at constant rate, from rest. It travels a distance of 20 m in 5 sec . The distance it will travel in next 5 sec will be
8. A bullet fired into a fixed target loses one-third of its velocity after penetrating 6 cm . How much further it will penetrate before coming to rest assuming that it faces constant resistance to motion?
9. A conveyor belt is moving horizontally at a speed of $(4 ~m / s)$. If a box of mass 30 kg is gently laid on it, it takes 0.1 second for the box to come to rest on the belt. The distance moved by the box on the conveyor belt (in m ) is
10. A bus, starts from rest, with a constant acceleration $(2 ~m / s^{2})$ and travels for 10 s . The distance travelled by it in last 3 seconds of its motion is
11. A body starts from rest and has an acceleration $(20 ~cm / s^{2})$. What is the distance covered by the body in first 8 s ?
12. Two cars $(A)$ and $(B)$ at rest at same point initially. If $(A)$ starts with uniform velocity of $(40 ~m / sec)$ and $(B)$ starts in the same direction with constant acceleration of $(4 ~m / s^{2})$, then B will catch A after how much time
13. At a certain a particle has a speed of $(18 ~m / s)$ in positive x -direction and 2.4 s later its speed was $(30 ~m / s)$ in the opposite direction. What is the magnitude of the average acceleration of the particle during the 2.4 s interval?
14. A particle experiences, constant acceleration for 20 second after starting from rest. If it travels a distance $(S_1)$ in the first 10 second and a distance $(S_2)$ the next 10 second, then
15. Tripling the speed of a motor car, multiplies the distance needed for stopping it by
16. Two cars $(A)$ and $(B)$ are moving in same direction with velocities $(30 ~m / s)$ and $(20 ~m / s)$. When car $(A)$ is at a distance d behind the car B , the driver of the car A applies brakes producing uniform retardation of $(2 ~m / s^{2})$. There will be no collision, when
17. An object accelerates from rest to a velocity $(27.5 ~m / s)$ in 10 sec , then find distance covered by object in next 10 sec.
18. A body starts with an initial velocity of $(10 ~m / s)$ and is moving along a straight line with constant acceleration. When the velocity of the particle is $(50 ~m / s)$, the acceleration is reversed in direction. The velocity of the particle, when it again reaches the starting point is
19. A body sliding on a smooth inclined plane requires 4 second to reach the bottom, starting from rest at the top. How much time does it take to cover one-fourth the distance starting from rest at the top?
20. A stone travels a distance of 25 m in the last second of its motion. It falls from a height of
21. An uniformly accelerated body travels a distance of 24 m in $(5^{th})$ second of its motion and 44 m in $(15^{th})$ sec of its motion. The acceleration of the particle will be
22. A body starting from rest moves with constant acceleration. The ratio of distance covered by the body during the $(5^{th})$ second to that covered in 5 seconds is
23. Velocity-time curves plotted for two bodies are straight lines passing through origin. The slope of v-t curve for two bodies X and Y is 3 and 2 respectively. In a given time interval, the ratio of displacement of X to that of Y is
24. A ball rolls from the top of a stair way with a horizontal velocity $(u ~m / s)$. If the steps are h m high and b m wide, the ball will hit the edge of the $(n^{th})$ step, if
25. A particle start moving from rest state along a straight line under the action of a constant force and travel distance $(x)$ in first 5 seconds. The distance travelled by it in next five seconds will be
26. A car, moving with a speed of $(50 ~km / hr)$, can be stopped by brakes after at least 6 m . If the same car is moving at a speed of $(100 ~km / hr)$, the minimum stopping distance is
27. A bullet fired into a fixed target loses one-third of its velocity after penetrating 6 cm . How much further it will penetrate before coming to rest assuming that it faces constant resistance to motion?
28. A body moving with a speed of $(10 ~m / s)$, long -Z - axis, experiences an acceleration of $(5 \hat{i}-3 \hat{j}+4 \hat{k} ~m / s^{2})$. Its displacement at the end of 2 s , is
29. A uniformly accelerated car, starting from rest, covers a distance S , in 4 sec. The distance it travels in next 4 sec, is
30. A bus, starts from rest, with a constant acceleration $(2 ~m / s^{2})$ and travels for 10 s . The distance travelled by it in last 3 seconds of its motion is
31. A ball is dropped from a bridge 125 meter above a river. After the ball has been falling for two second, a second ball is thrown straight down after it. What must its initial velocity be so that both hit the water at the same time? $((g=10 ~m / s^{2}))$
32. A body is moving with uniform acceleration describes 40 m in the first 5 sec and 65 m in next 5 sec . Its initial velocity will be
33. At a certain a particle has a speed of $(18 ~m / s)$ in positive x -direction and 2.4 s later its speed was $(30 ~m / s)$ in the opposite direction. What is the magnitude of the average acceleration of the particle during the 2.4 s interval?
34. The initial velocity of a body moving along a straight line is $(7 ~m / s)$. It has a uniform acceleration of $(4 ~m / s^{2})$. The distance covered by the body in the $(5^{th})$ second of its motion is
35. A body covers $(20 ~m)$, $(22 ~m)$, $(24 ~m)$, in $(8^{th})$, $(9^{th})$ and $(10^{th})$ seconds respectively. The body starts (1) from rest and moves with uniform velocity. (2) from rest and moves with uniform acceleration. $(3)$ with an initial velocity and moves with uniform acceleration. (4) with an initial velocity and moves with uniform velocity.