EASY
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A particle of mass m is moving in the space under the influence a force F=v×A, where v is the velocity of particle and A is constant vector, given as A=Ak^. At t=0, particle is at origin and moving with initial velocity v0=v1i^+v2k^. Choose the CORRECT statement(s).

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Important Questions on Laws of Motion

HARD
A helicopter rises from rest on the ground vertically upwards with a constant acceleration g. A food packet is dropped from the helicopter when it is at a height h. The time taken by the packet to reach the ground is close to [g is the acceleration due to gravity]:
MEDIUM

Two skaters, P and Q are skating towards each other. Skater, P throws a ball towards, Q every 5 s such that it always leaves her hand with speed 2 m s-1 with respect to the ground. Consider two cases: (I) P runs with speed 1 m s-1 towards Q, while Q remains stationary. (II) Q runs with speed 1 m s-1 towards P, while P remains stationary. Note That irrespective of speed of P, ball always leaves P s hand with speed 2 m s-1 with respect to the ground. Ignore gravity. Balls will be received by Q.

EASY
Motion of a particle in x-y plane is described by a set of following equations x=4sinπ2-ωt m and y=4sinωt m. The path of the particle will be
HARD

Three balls, A, B and C are released and all reach the point X (shown in the figure). Balls A and B are released from two identical structures, one kept on the ground and the other at height h from the ground as shown in the figure. They take time tA and tB respectively to reach X (time starts after they leave the end of the horizontal portion of the structure). The ball C is released from a point at height h vertically above X and reaches X in time tC. Choose the correct statement.

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MEDIUM
The displacement x (in meter) of a particle of mass m (in kg) moving in one dimension under the action of a force, is related to time t (in sec) by t=x+3. The displacement of the particle when its velocity is zero, will be
EASY

The given graph shows the variation of velocity v with position x for a particle moving along a straight line

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Which of the following graph shows the variation of acceleration a with position x?

MEDIUM

When a particle moves with variable velocity, which of the following statement are NOT correct ?
(i) Average speed = average velocity
(ii) Instantaneous speed = instantaneous velocity
(iii) Distance covered = magnitude of displacement

MEDIUM
For uniform acceleration in rectilinear motion, which of the following is not correct?
HARD
Mark the correct statement(s).
EASY
A particle of mass 2 kg moves on a circular path with constant speed 10 m s-1. Find change in speed and magnitude of change in velocity. When particle completes half revolution.
MEDIUM
Two bodies are thrown with the same initial speed at angles α and 90-α with the horizontal. What will be horizontal ranges?
EASY
What is rectilinear motion?
HARD
From a lift moving upwards with a uniform acceleration a=2 m s-2, a man throws a ball vertically upwards with a velocity v=12  m s-1 relative to the lift. The ball comes back to the man after a time t. Find the value of t in seconds.
EASY
What are different types of motions?
MEDIUM

Represent the union of two sets by Venn diagram for each of the following.

X={x | x is a prime number between 80 and 100}

Y={y | y is an odd number between 90 and 100}

MEDIUM
A body moves with a constant velocity of 50 m s-1 from the point 3,4 m in a direction of 3i^+4j^. The position vector of the body at t=3 s is :
MEDIUM

Which of the following statements are correct?

EASY
In which of the following examples of motion, can the body be considered approximately a point object:
MEDIUM
A block of mass 15 kg is placed on a long trolley. The coefficient of static friction between the block and the trolley is 0.18. The trolley accelerates from rest with 0.5 m s-2 for 20 s and then moves with uniform velocity. Discuss the motion of the block as viewed by an observer is moving with the trolley.
HARD
A lift is coming from 8th floor and is just about to reach 4th floor. Taking ground floor as Origin and positive direction upwards for all quantities, which one of the following is correct?