11.

A body of mass 0.1 kg attains a velocity of 10 ms' in 0.1 sec. The force acting on the body is

• 10N

• 0.01N

• 0.1N

• 100N

If force $\overrightarrow{\mathrm{F}}=5\hat{\mathrm{i}}+3\hat{\mathrm{j}}+4\hat{\mathrm{k}}$ makes a displacement of $\overrightarrow{\mathrm{s}}=6\hat{\mathrm{i}}-5\hat{\mathrm{k}}$work done by the force is

• 10units

• $122\sqrt{5}$units

• $5\sqrt{122}\mathrm{units}$

• 20units

The angular velocity of second hand clock, of a clock is

• $\left(\frac{\mathrm{\pi }}{6}\right)\mathrm{rad} {\mathrm{s}}^{-1}$

• $\left(\frac{\mathrm{\pi }}{60}\right)\mathrm{rad} {\mathrm{s}}^{-1}$

• $\left(\frac{\mathrm{\pi }}{30}\right)\mathrm{rad} {\mathrm{s}}^{-1}$

• $\left(\frac{\mathrm{\pi }}{15}\right)\mathrm{rad} {\mathrm{s}}^{-1}$

A body is moving in a circular path with acceleration 'a'. If its velocity gets doubled, find the ratio of acceleration after and before the change 

• 1:4

• $\frac{1}{4}:1$

• 2:1

• 4:1

Acceleration due to gravity at earth's surface is 'g'ms^-2 . Find the effective value of gravity at a height of 32 km from sea level (R_e=6400km)

• 0.5 gms^-2

• 0.99 gms^-2

• 1.01 gms^-2

• 0.90 gms^-2

Near earth's surface, time period of a satelliteis 4 hrs. Find its time period at height '4R' from the centre of earth

• 32 hrs

• $\left(\frac{1}{8\sqrt[3]{2}}\right)\mathrm{hrs}$

• 8$\sqrt[3]{2}$hrs

• 16hrs

A girl is swinging on a swinging plate form in sitting position when the girl stands up then the period of swinging?

• Will not change

•  Will depend on height of girl

• Will be longer

•  Will be shorter

The displacement of the motion of a particle is represent by a equation  $\mathrm{Y}=\mathrm{ASin\omega t}+\mathrm{BCos\omega t}$. The motion of the particle is

• SHM with amplitude $\sqrt{{\mathrm{A}}^2+{\mathrm{B}}^2}$

• SHM with amplitude A+B

• SHM with amplitude A

• Oscillatory but not in SHM

A ball falling in a lake depth 200 m shows a decrease of 0.1 % in its volume at the bottom then the bulk modulus of the material of the ball is

• $19.6\times {10}^8 \mathrm{N}/{\mathrm{m}}^2$

• $19.2\times {10}^7\mathrm{N}/{\mathrm{m}}^2$

• $24\times {10}^9 \mathrm{N}/{\mathrm{m}}^2$

• $24\times {10}^5 \mathrm{N}/{\mathrm{m}}^2$

A fixed volume of iron is drawn into a wire of length l. The extension x produced in this wire by a constant force F is proportional to

• l

• $\frac{1}{\mathrm{l}}$

• ${\mathrm{l}}^2$

• $\frac{1}{{\mathrm{l}}^2}$