Motion under gravity

The position of a particle is given by  $x\left(t\right)=3t+0.5t^3m$  . Find instantaneous velocity at t=2s.
 
.

• 6m/s

• 4m/s

• 9m/s

• 15m/s

What is the acceleration due to gravity at the Moon’s surface? Moon’s mass = 7.35 x 10²² kg, the radius of the Moon is 1.7 x 10⁶ m, universal constant is 6.67 x 10^-11 N m² / kg²

• 16.19m/s²

• 1.62m/s²

• 1.62m/s

• 16.19m/s

Acceleration due to gravity at a place is independent of object's

• mass

• density

• shape

• all of the above

the value of g changes with shape of Earth. The statement is

• true

• False

• vague

• none of the above

Value of g at the center of Earth is

• Zero

• 9.8m/s²

• 10.00m/s²

• None of the above

in a simple pendulum, the centre of mass of the bob ( oscillating mass) is known as

• centre of suspension

• centre of oscillation

• centre of gravity

• All of the above

Length of simple pendulum means the distance from the centre of suspension and centre of

• Oscillation

• gravity

• None of the above

The perpendicular distance that constitute a couple, that bring the pendulum back to the equilibrium position is

• L tanΘ

• L cosΘ

• L sinΘ

• L CotΘ

Oscillations of a simple Pendulum are of ..................... nature

• Complex

• unharmonic

• harmonic

• None of the above

Acceleration due to gravity of a simple pendulum is given by

• 4π L/T²

• 4π² L²/T

• 2π² L/T²

• 4π² L/T²