Answer:
Option B is correct.
Explanation:
Potential energy or chemical potential energy is used to Cook food which is then converted into thermal energy. The type of energy used also depends upon the type of cooking appliances used.
For e.g. stove convert potential energy to thermal energy.
(a) 
The radiation pressure exerted by an electromagnetic wave on a surface that totally absorbs the radiation is given by

where
I is the intensity of the wave
c is the speed of light
In this problem,

and substituting
, we find the radiation pressure

(b) 
Since we know the cross-sectional area of the laser beam:

starting from the radiation pressure found at point (a), we can calculate the force exerted on a tritium atom:

And then, since we know the mass of the atom

we can find the acceleration, by using Newton's second law:

3) a stretched rubber band
Answer:
A
Explanation:
1. When the block moves across a table top, F(pulling) = - F(frictional).
Sum of this forces = 0, so the block moves with uniform speed.
2. When the block is pulled on top of the table covered with beads
F(pulling) > - F(frictional).
So, the sum of forces (∑F) is a number that is more than 0 and directed to the direction of movement.
So, a = ∑F / m is positive and constant. Speed is increasing because
v(t) = v(0)+at
a is constant and directed forward.
That means a is acceleration, and constant.