The radius of the Moon's orbit is 385000 km. It takes 27 days for the Moon to complete one orbit.
Calculate the orbital speed of the Moon.
Give a suitable unit.

can someone please explain this. the question also was asked to use it from the center of earth

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies.

(2) (a) you have a simple circuit that consists of only a battery (δvbat=1.5v) and two resistors with resistance r1=10ω and r2=5ω, connected in series with each other. what is the current running through the battery? (b) you re-arrange your circuit so now r2 is attached in parallel to r1 rather than in series. what is the current running through the battery? (c) you add an additional resistor r3=7ω on the same branch as r2. what is the current running through the battery? (d) what is the power dissipated in r3?

What is the weight of a feather (mass = 0.0001 kg) that floats through earth's and the moon's atmospheres?