Answer:
F = 1400 N
Explanation:
It is given that,
Mass of the ball, m = 70 kg
It is moving with an acceleration of 20 m/s². We need to find the force exerted by the ball.
Force is given by the product of mass and acceleration. So,
F = ma

So, the force of 1400 N is exerted by a metal ball.
Answer:
Frequency, 
Explanation:
We have,
Speed of radio waves is 
Wavelength of radio waves is 
It is required to find the frequency of the radio waves. The speed of a wave is given by :

So, the frequency of the radio wave is
.
Answer:
The centripetal force on body 2 is 8 times of the centripetal force in body 1.
Explanation:
Body 1 has a mass m, and its moving in a circle with a radius r at a speed v. The centripetal force acting on it is given by :

Body 2 has a mass 2m and its moving in a circle of radius 4r at a speed 4v. The centripetal force on body 2 is :

So, the centripetal force on body 2 is 8 times of the centripetal force in body 1.
Explanation:
The formula to determine the eccentricity of an ellipse is the distance between foci divided by the length of the major axis
Answer:
Force = Mass x Acceleration
Explanation: