A player caught a cricket ball of mass $$150$$ $$g$$ moving at a rate of $$20$$ $$m/s.$$ If the catching process is completed in $$0.1s,$$ the force of the blow exerted by the ball on the hand of the player is equal to

Consider a two particle system with particles having masses $$m_1$$ and $$m_2$$. If the first particle is pushed towards the center of mass through a distance $$d,$$ by what distance should the second particle is moved, so as to keep the center of mass at the same position?

A bomb of mass $$16kg$$ at rest explodes into two pieces of masses $$4$$ $$kg$$ and $$12$$ $$kg.$$ The velocity of the $$12$$ $$kg$$ mass is $$4m{s}^{-1}.$$ The kinetic energy of the other mass is

If the terminal speed of a sphere of gold (density $$=19.5kg/m^3$$) is $$0.2$$ $$m/s$$ in a viscous liquid (density $$=1.5kg/m^3$$, find the terminal speed of a sphere of silver (density $$=10.5kg/m^3$$) of the same size in the same liquid

A wire elongates by $$l$$ $$mm$$ when a LOAD $$W$$ is hanged from it. If the wire goes over a pulley and two weights $$W$$ each are hung at the two ends, the elongation of the wire will be (in $$mm$$)

In a common base mode of a transistor, the collector current is $$5.488$$ $$mA$$ for an emitter current of $$5.60mA.$$ The value of the base current amplification factor $$\left(\beta \right)$$ will be

If the lattice constant of this semiconductor is decreased, then which of the following is correct?

In the following, which one of the diodes is reverse biased?

The circuit has two oppositively connected ideal diodes in parallel. What is the current following in the circuit?

A solid which is not transparent to visible light and whose conductivity increases with temperature is formed by

If the ratio of the concentration of electrons to that of holes in a semiconductor is {7 \over 5} and the ratio of currents is {7 \over 4}, then what is the ratio of their drift velocities?

The maximum velocity of a particle, executing simple harmonic motion with an amplitude $$7$$ $$mm,$$ is $$4.4$$ $$m/s.$$ The period of oscillation is

A coin is placed on a horizontal platform which undergoes vertical simple harmonic motoin of angular frequency $$\omega .$$ The amplitude of oscillation is gradually increased. The coin will leave contact with the platform for the first time

Starting from the origin a body oscillates simple harmonically with a period of $$2$$ $$s.$$ After what time will its kinetic energy be $$75\%$$ of the total energy?

The $$rms$$ value of the electric field of the light coming from the Sun is $$720$$ $$N/C.$$ The average total energy density of the electromagnetic wave is

A particle of mass $$100g$$ is thrown vertically upwards with a speed of $$5$$ $$m/s$$. The work done by the force of gravity during the time the particle goes up is

A ball of mass $$0.2$$ $$kg$$ is thrown vertically upwards by applying a force by hand. If the hand moves $$0.2$$ $$m$$ while applying the force and the ball goes upto $$2$$ $$m$$ height further, find the magnitude of the force. (consider $$g=10m/s^2$$).

A mass of $$M$$ $$kg$$ is suspended by a weightless string. The horizontal force that is required to displace it until the string makes an angle of $$45^{\circ }$$ with the initial vertical direction is

The potential energy of a $$1$$ $$kg$$ particle free to move along the $$x$$-axis is given by V\left( x \right) = \left( {{{{x^4}} \over 4} - {{{x^2}} \over 2}} \right)J. The total mechanical energy of the particle is $$2J.$$ Then, the maximum speed (in $$m/s$$) is

In a series resonant $$LCR$$ circuit, the voltage across $$R$$ is $$100$$ volts and $$R=1k\Omega$$ with $$C=2\mu F.$$ The resonant frequency $$\omega$$ is $$200$$ $$rad/s$$. At resonance the voltage across $$L$$ is