Answer:
gather the data needed to make the forecast
Explanation:
Given that,
(a) Work done by the electric field is 12 J on a 0.0001 C of charge. The electric potential is defined as the work done per unit charged particles. It is given by :



(b) Similarly, same electric field does 24 J of work on a 0.0002-C charge. The electric potential difference is given by :



Therefore, this is the required solution.
Answer:
a) 3.9 x 10⁻⁵ kg
Explanation:
The amount of mass required to produce the energy can be given by Einstein's formula:

where,
m = mass required = ?
E = Energy produced = 3.5 x 10¹² J
c = speed of light = 3 x 10⁸ m/s
Therefore,

Hence, the correct option is:
<u>a) 3.9 x 10⁻⁵ kg</u>
Explanation:
Given that,
Mass if the rock, m = 1 kg
It is suspended from the tip of a horizontal meter stick at the 0-cm mark so that the meter stick barely balances like a seesaw when its fulcrum is at the 12.5-cm mark.
We need to find the mass of the meter stick. The force acting by the stone is
F = 1 × 9.8 = 9.8 N
Let W be the weight of the meter stick. If the net torque is zero on the stick then the stick does not move and it remains in equilibrium condition. So, taking torque about the pivot.

W = 3.266 N
The mass of the meters stick is :

So, the mass of the meter stick is 0.333 kg.