Answer:
Intensity, 
Explanation:
Power of the light bulb, P = 40 W
Distance from screen, r = 1.7 m
Let I is the intensity of light incident on the screen. The power acting per unit area is called the intensity of the light. Its formula is given by :




So, the intensity of light is
.
Answer:0.38
Explanation:
the formula is f = c / λ
so f= 2.5/6.5
and that equals 0.38 46 and so on so i just rounded it
Answer:

Explanation:
F = Magnetic force = 4.11 N
= Net current
= Current in one of the wires = 7.68 A
B = Magnetic field = 0.59 T
= Angle between current and magnetic field = 
= Length of wires = 2.64 m
= Current in the other wire
Magnetic force is given by

Net current is given by

The current I is
.