Quiz 2 (Force and force in nature)
Instruction: Do all problems and show your work in detail and step by step (20 marks)
(Given: earth radius = 6,400 km, mass of earth = 6x1034 kg, G=6.67x10-11 Nm/kg)
1.
Two objects mass 10 and 30 kg are 2 m. apart. How much is gravitational force between these two objects?
(2 marks)
2.
An object mass 120 kg is now at a distance 4 times of radius of the earth from the center of earth. How much is
weight of this object now? (2 marks)
3.
An object weight 50 N at a distance 4 times of radius of the earth from the surface of earth. How much is weight
of this object at earth surface? (3 marks)
A magnet bar is placed as shown in the diagram below. If four compasses are placed at point A, B, C and D,
match the correct compass 1, 2, 3 or 4 on point A, B, C to D. (Hint: Compass can be used more than once)
4.
A=
B =.
C =
D =
3
4