Answer:
(A) 3.1 m/s
(B) 2.0 s
Explanation:
At the minimum speed, the force of gravity equals the centripetal force.
mg = m v² / r
v = √(gr)
v = √(9.8 m/s² × 1.0 m)
v = 3.1 m/s
The time is the circumference divided by the speed.
t = (2π × 1.0 m) / (3.1 m/s)
t = 2.0 s
Answer:

Explanation:
From the question we are told that
The electric filed is
Generally according to Gauss law
=> 
Given that the electric field is pointing downward , the equation become

Here
is the excess charge on the surface of the earth
is the surface area of the of the earth which is mathematically represented as

Where r is the radius of the earth which has a value 
substituting values


So

Here
s the permitivity of free space with value

substituting values


Answer:
Explanation:
Gravitational Potential Energy at earth surface 
Gravitational Potential Energy at height h is 
Energy required to lift the satellite 

Now Energy required to orbit around the earth



(given)




(b)For greater height
is greater than 
thus energy to lift the satellite is more than orbiting around earth
Think of a wedge as something you put in between objects, so it is a separates objects