Physics Aptitude JEE

An elevator is moving up with uniform velocity. In the elevator frame of reference, the direction of pseudo force is?

• 
• 
• pseudo force is zero

Value of friction force acting between a block and floor is?

• $\mu N$

• $>\mu N$

• $0\le f\le\mu N$

Work done by all the forces is equal to = change in ________

• potential energy

• kinetic energy

• mechanical energy

• total energy

Value of g ( in $ms^2$ )  at the centre of the earth is?

• 9.8

• <9.8 but not ZERO

• >9.8

• ZERO

A stretched copper wire is under___________

• longitudinal stress

• shear stress

• volume stress

• compressive stress

While using the formula $F=V\rho g$  for calculating buoyant force, what density stand for?

• density of the immersed object

• density of the displaced liquid

When a spherical object is under pure rolling on a rough floor with uniform velocity, which of the following is true about friction acting at the bottom most point?

• 
• 
• ZERO

• forward, backward or ZERO

Velocity and acceleration vectors at the topmost point of a ground to ground projectile are______

• parallel

• anti-parallel

• perpendicular

The equation $v=u+at$ , be applied if acceleration is produced by a spring force.

• TRUE

• FALSE

Centre of mass of an object must be present within the bulk of the object.

• 
•