atomic physics

1. Statement 1 is consistent. The higher the light intensity, more photoelectrons are produced.

2. Statement 1: the alpha particles will encounter more atoms if a thick foil is used.
Statement 2: Higher kinetic energy of alpha particles means higher particle speed, hence leading to shorter interaction time between the particles and the electric field of the nucleus.
Statement 3: Higher atom number means more protons present in the nucleus. Hence larger repulsive force given to the alpha particles.

3. The electric force direction follows the field lines, which are extending radially outward from the nucleus. Clearly, the force shown in option C is NOT in a direction from the centre of the nucleus.