An object is dropped from rest from a height of 4.4 107 m above the surface of the Earth. If there is no air resistance, what is its speed when it strikes the Earth?

Explanation:

An object is drop from a height, then it is in direction of gravity

g is +ve

When an object drop from a height, the initial velocity is 0,

U=0

Given that h=4.4×10^7m

V=?

g=9.81m/s^2

Then using equation of motion

V^2=U^2+2gh

V^2=0+2×9.81×4.4×10^7

V^2=86.33×10^7m/s

Take square root of both side

V=29381.63m/s

Now to km/s, divide by 1000

Since 1km=1000m

V=29.38km/s

answer: d. a cme increases the amount of energy in the solar wind

explanation:

coronal mass ejections, also called cmes, are large clouds of plasma and magnetic field that erupt from the sun. only when the cloud is aimed at earth will the cme hit earth and therefore cause impacts. high-speed solar wind streams come from areas on the sun known as coronal holes.