1.

In an orbital motion, the angular momentum vector is

• along the radius vector

• parallel to the linear momentum

• in the orbital plane

• perpendicular to the orbital plane

The direction of the angular velocity vector is along

• the tangent to the circular path

• the inward radius

• the outward radius

• the axis of rotation

Which of the following velocity-time graphs shows a realistic situation for a body in motion?

A bomb of mass 3.0 kg in air into two pieces of masses 2.0 kg and 1.0 kg. The smaller mass goes at speed of 80 m/s. The total energy imparted to the two fragments is

• 1.07 kJ

• 2.14 kJ

• 2.4 kJ

• 4.8 kJ

Using mass (M), length (L), time (T) and current (A) as fundamental quantities, the dimension of permittivity is

• [ M L^-2 T² A ]

• [ M^-1 L^-3 T⁴ A² ]

• [ M L T^-2 A ]

• [ M L² T^-1 A² ]

Assertion: The driver in a vehicle moving with a constant speed on a straight road is in a noninertial frame of reference.

Reason: A reference frame in which Newton's laws of motion are applicable is non-inertial.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

The waves produced by a motorboat sailing in water are

• transverse

• longitudinal

• longitudinal and transverse

• stationary

A sphere of mass Mand radius R is falling in a viscous fluid. The terminal velocity attained by the falling object will be proportional to

• R²

• R

• 1/R

• 1/R²

Two springs are connected to a block mass M placed on a frictionless surface as shown in figure. If both the springs have a spring constant k, the frequency of oscillation of the block is

Suppose the sun expands so that its radius becomes 100 times its present radius and its surface temperature becomes half of its present value. The total energy emitted by it then will increase by a factor of

• 10⁴

• 625

• 256

• 16