Gravity obeys the inverse square law. At 6400 km above the center of the Earth (Earth's surface) you weigh x. Twice that reduces your weight to 1/4th. Four times that height reduces your weight to 1/16th. 4 times 6400 km is 25,600 km. But that is above the center of the earth, and the question requests the height above the surface, so we deduct 6400 km to arrive at our final answer: 19,200 km.
Incidentally, it doesn't exactly work the opposite way. At the center of the Earth the mass would be equally distributed around you, and you would therefore be weightless.
Answer:twice of initial value
Explanation:
Given
spring compresses
distance for some initial speed
Suppose v is the initial speed and k be the spring constant
Applying conservation of energy
kinetic energy converted into spring Elastic potential energy

When speed doubles

divide 1 and 2


Therefore spring compresses twice the initial value
Answer:
The angular velocity of the propeller is 2.22 rad/s.
Explanation:
The angular velocity (ω) of the propeller is:
Where:
θ: is the angular displacement = 10.6 revolutions
t: is the time = 30 s

Therefore, the angular velocity of the propeller is 2.22 rad/s.
I hope it helps you!
Answer:
Option 3
Explanation:
O Option C is NEGATIVELY CHARGED, meaning it has GAINED ELECTRONS resulting in a GREATER number of ELECTRONS than PROTONS.
The term period (symbol: T) describes the time it takes for an object to complete one full cycle of motion on a spring.
The formula for time is: T = 1 / f , where f is the frequency , f= c / λ = wave speed c (m/s) / wavelength λ (m)..
The formula describes that as the frequency of a wave increases, the time period of the wave decreases.