Answer:
the tension in the string an instant before it broke = 34 N
Explanation:
Given that :
mass of the ball m = 300 g = 0.300 kg
length of the string r = 70 cm = 0.7 m
At highest point, law of conservation of energy can be expressed as :


The tension in the string is:

Thus, the tension in the string an instant before it broke = 34 N
F=mg=Gm1m2/r^2
g=Gm2/r^2
g=2Gm2/(2r)^2=2Gm2/4r^2=Gm2/2r^2
So since there is half times the gravity on this unknown planet that has twice earth's mass and twice it's radius, then the person can jump twice as high. 1.5*2= 3m high
Answer:
Since the ball becomes positively charged, it will repel as like charges repel.
Answer:
d) Wind
Explanation:
Secondary energy is energy produced by converting energy available in its natural state in the environment. Hence Wind is a primary source not a secondary source