Answer:
Pinhole Projection
Explanation:
You will get a great view if you project a sunlight coming thrugh a small hole onto a viewing card enclosed in a long box. The smaller the pinhole, the sharper the image
Answer:
-100N
Explanation:
Newton's third law of motion states that to every force exerted on one body, there is an equal and opposite force. This means that if object A exerts an ACTION force on B, there is a force called REACTION FORCE, which is equal and opposite, exerted on A by B.
The action and reaction forces are equal in size/magnitude but opposite in direction. In this case where a tennis racket strikes a tennis ball with a force (action force) of 100N, the ball will strike the racket with a reaction force of -100N.
F(RB) = -F(BR)
The 4 significant figures of 31,546,000 are all 8 of the digits.
Answer:
Resistance of the iron rod, R = 0.000077 ohms
Explanation:
It is given that,
Area of iron rod, 
Length of the rod, L = 35 cm = 0.35 m
Resistivity of Iron, 
We need to find the resistance of the iron rod. It is given by :



So, the resistance of the rod is 0.000077 ohms. Hence, this is the required solution.