Physics Test 20...

A man in a balloon rising vertically with an acceleration of 4.9 m/sec² releases a ball 2 sec after the balloon is let go from the ground. The greatest height above the ground reached by the ball is  (g = 9.8 m/sec²)

The (x, y, z) coordinates of two points A and B are given respectively as (0, 4, -2) and (-2, 8, -4). The displacement vector from A to B is:

A man in a balloon, throws a stone downwards with a speed of  5 m/s with respect to balloon . The balloon is moving upwards with a constant acceleration of 5 m/s². Then velocity of the stone relative to the man after 2 second is :

If a body starts at rest and moves for five seconds to cover a distance of 25 m with uniform acceleration a, then a is

Which of the following statements about a particle’s position is true if x = (4t² – 8t) ?

A particle of mass 1 kg is hanging from a spring of force constant 100 Nm^-1. The mass is pulled slightly downward and released, so that it executes free simple harmonic motion with time period T. The time when the kinetic energy and potential energy of the system will become equal is  The value of x is _______. (in integers)

If the vectors 6i - 2j + 3k, 2i + 3j- 6k and 3i + 6j- 2k form a triangle, then it is

A body of mass M at rest explodes into three pieces, in the ratio of masses 1 : 1 : 2. Two smaller pieces fly off perpendicular to each other with velocities of 30 ms-1 and 40 ms-1 respectively. The velocity of the third piece will be:

If x = 5t + 3t² andy = 4t are the x and y co-ordinates of a particle at any time t second where x and y are in metre, then the acceleration of the particle

A bird flies from (-3m, 4m, -3m) to (7m, -2m, -3m) in the xyz- coordinates. The bird's displacement vector is given by