Hot water poured into a thick glass bottle may result in the cracking of the bottle because

A wire 1.2 m long 20$${}^{oC}$$ increases in length by 2 cm when heated to 520 $${}^{oC}$$. Calculate its linear expansivity?

A box of mass 45 kg is given an initial speed of 5 ms⁻¹ and it slides along a horizontal surface a distance of 3 m before coming to rest. Calculate the coefficient of dynamic friction between the box and the surface. [Take $g=10{\text{ms}}^{-2}$]

Calculate the centripetal force acting on the electron.

An object of volume $$400c{m}^3$$ and density $$2.5gc{m}^{-3}$$is suspended from a spring balance with half Its volume immersed in water. Determine the reading on the spring balance.

[ Density of water =$$1gc{m}^{-3}$$]

A progressive wave equation is given by y = 0.2 $$\sin (200\pi t-10\pi x)$$, where y is in metres and t in seconds. Determine the frequency and speed of the wave.

Which of the following is not a unit of acceleration?

The magnetic field strength at a point close to and lying along the axis of a solenoid will be greatest if the core of the solenoid is made up of:

A water pump rated 1200 W lifts water to a height of 60m in 10 s. Calculate the mass of water lifted. [g = 10 $$m{s}^{-2}$$]

The standing wave of a string vibrating at its fundamental frequency has

Which of the following statements is not correct about the astronomical telescope in normal use?

In stringed instruments, the highest pitched notes are produced by

The difference between a crystalline solid and an amorphous solid is that a crystalline solid

Which of the following materials is used to shield radioactive fallout?

A mass of gas at constant temperature occupies 200 $$c{m}^3$$ at a pressure of 76 cm Hg. If the pressure is increased by 50%, the volume will