Question
The ozone layer absorbs
|
(a) Infrared radiations |
(b) Ultraviolet radiations |
(c) X-rays |
(d) g-rays |
✓
Answer
(b) Ultraviolet radiations
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
An antenna behaves as resonant circuit only when its length is
|
(a) |
(b) |
|
(c) |
(d) |
Biot-Savart law indicates that the moving electrons (velocity v) produce a magnetic field B such that:
The value of $(\mu_{0}\in_{0})^{-1/2}$ is :
→Light is an electromagnetic wave. Its speed in vacuum is given by the expression
|
(a) |
(b) |
(c) |
(d) |
The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light:
The variation of magnetic susceptibility (x) with temperature for a diamagnetic substance is best represented by
|
(a)
|
(b)
|
(c)
|
(d)
|
Magnetic flux during time interval $\tau$ varies through a stationary loop of resistance R, as $\phi_\text{B}=\text{at}(\tau-\text{t})$ Find the amount of heat generated during that time. Neglect the inductance of the loop.
→A charge + q is sent through a magnetic field. The force acting on it is maximum when the angle between the direction of motion of the charged particle and the magnetic field:
Carbon -14 decays with half-life of about 5,800 years. In a sample of bone, the ratio of carbon -14 to carbon -12 is found to be 
of what it is in free air. This bone may belong to a period about x centuries ago, where x is nearest to
|
(a) 2 × 58 |
(b) 58 |
(c) 58/2 |
(d) 3 × 58 |
An electric field is applied to a semiconductor. Let the number of charge carriers be n and the average drift speed be v. If the temperature is increased,