Physics Test - ...

If in the following figure, the height of the object is \(H_{1}=+2.5 \mathrm{~cm}\), then the height of image \(H_{2}\) formed is:

If the force on a moving body is always uniform and perpendicular to its motion, then:

The bob of a simple pendulum is a spherical hollow ball filled with water. A plugged hole near the bottom of the oscillating bob gets suddenly unplugged. During observation, till water is coming out, the time period of oscillation would

One kilowatt-hour is unit of:

When an object is heated, the molecules of that object:

A Carnot engine works as a refrigerator between 250 K and 300 K. If it receives 750 calories of heat from the reservoir at the lower temperature, then the amount of heat rejected at the higher temperature is

F₁ and F₂ are focal lengths of the objective and the eyepiece of a telescope, respectively. The angular magnification for this telescope is equal to

An observer is moving towards a stationary source with 1/10 the speed of sound. The ratio of apparent frequency to real frequency is

The disc of a siren containing 60 holes rotates at a constant speed of 360 rpm. The emitted sound is in unison with a tuning fork of frequency

A police car horn emits sound at a frequency of 240 Hz when the car is at rest. If the speed of sound is 330 m/s, the frequency heard by an observer who is approaching the car at a speed of 11 m/s, is