Question

True and false

1. All Waves require a medium for transporting energy.
2. A tuning fork cannot be made to vibrate unless it is struck.
3. Unlike charges repel.
4. An object in an electric field cannot have any potential energy due to the field.
5. Magnetic forces are a maximum when a moving charged particle travels perpendicular to magnetic field lines.
6. When the speed of light increases in going from one medium to another,the light bends away from the normal.
7. AM waves are less susceptible to static than FM waves.
8. Diffraction limits the magnification of a small lens or mirror.
9. The speed of light in a transparent media varies with frequency.
10.A converging lens is thickest at the center.

Answer 1

1. not all waves require medium to transport energy for example electromagnetic waves that do not require medium they can also travel through vacuum

So this is false.

2. Yes this is true tuning fork cannot make vibrations unless it is struck.

This is true.

3. According to coulombs law unlike charges attract each other.

thus this is false

4. electric field lines corresponding to some potential electric field and electric potential are related. The object in the electric field have some potential associated with it

thus this is false.

5. Magnitude magnetic force acting on charge is given by

Thus force will be maximum if is 900.

Magnetic forces are a maximum when a moving charged particle travels perpendicular to magnetic field lines.

This is true.

6.When the speed of light increases in going from one medium to another,the light bends away from the normal.

When speed of light decreases then the light ray bends towards the normal.

This is true

7. AM is more susceptible to noise because noise affects amplitude. FM is less susceptible to noise because information in an FM signal is transmitted through varying the frequency, and not the amplitude. Thus AM is less susceptible to static.

This is true.

8. Diffraction limits the resolution between two objects not the magnification.

This is false

9. The velocity of light is given by V=frequncy×wavelength

Now if the frequency varies then speed should also vary.

This is true.

10.Yes converging lens i.e. convex lens is thickest at the centre. While the diverging lens is thin at centre.

This is true.