A body is moved along a straight line by a machine delivering constant power. The distance travelled by the body in  time t is proportional to

• t^1/2

• t

• t^3/2

• t²

P, Q and R are three coplanar forces acting at a point and are in equilibrium. Given: P = 1.9318 kg wt [sin θ₁ = 0.9659], the value of R (in kg wt) is

• 0.9659

• 2

• 1

• 1/2

173.

If a solid sphere of mass 1 kg and radius 0.1 m rolls without slipping at a uniform velocity of I m/s along a straight line on a horizontal floor, the kinetic energy is

•  J

•  J

• $\frac{7}{10}$ J

• 1 J

The voltage of clouds is 4 x 10 volt with respect to ground. In a lightening strike lasting 100 msec, a charge of 4 coulombs is delivered to the ground. The power of the lightning strike is

• 160 MW

• 80 MW

• 20 MW

• 500 MW

For inelastic collision between two spherical rigid bodies

• the total kinetic energy is conserved

• the total potential energy is conserved

• the linear momentum is not conserved

• the linear momentum is conserved

A person used force (F), shown in figure to move a load with constant velocity on surface. Identify the correct surface profile.

A block of mass 10 kg is moving in x-direction with a constant speed of 10 m/sec. It is subjected to a retarding force F = -0.1 x joule/meter during its travel from x = 20 meter to x = 30 meter. Its final kinetic energy will be

• 475 joule

• 450 joule

• 275 joule

• 250 joule

A solid sphere is rolling on a frictionless surface, show in figure with a translational velocity v m/s. If it is to climb the inclined surface then v should be

• ≥ $\sqrt{\raisebox{1ex}{$10$}\!\left/ \!\raisebox{-1ex}{$7\mathrm{gh}$}\right.}$

• ≥ $\sqrt{2\mathrm{gh}}$

• 2gh

• 10/7 gh

A horizontal platform is rotating with uniform angular velocity around the vertical axis passing through its centre. At some instant of time a viscous fluid of mass 'm' is dropped at the centre and is allowed to spread out and finally fall. The angular velocity during this period

• decreases continuously

• decreases initially and increases again

• remains unaltered

• increases continuously

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