Question

I have two I need help with!

1. An airplane is flying in a horizontal flight level at constant velocity, heading due east. If the weight of the plane is 2.6 x 10^4 N, what is the net force on the plane?
a)-2.6x10^4 N
b)2.6x10^4 N
c)0.0 N
d) that due to gravity, which is 2.5x10^5 N
e)need to know the thrust, drag, and buoyant force

2a.A 320-kg satellite is in orbit around the earth 16,000km above the earths surface. What is the weight of the satellite when in orbit
a)314 N
b) 320 kg
c) 120 N
d)250 N
e)498 N
2b.Whats the weight of the same satellite when it is on the earths surface, just before being launched?
a)320kg
b)320 N
c) 32.7 N
d)512 N
e) 3100 N

Answer 1

1. Constant velocity means zero net force.

2a. Weight is measured in Newtons, not kg.
W = M g', where g' is less than the value at the earth's surface, g. 16000 km above the Earth's surface is about 22,400 above the center of the Earth, or 3.5 Earth radii. g' = g/(3.5)^2 = 0.80 m/s^2
W = about 250 N

2b. M g = ?
The closest answer is (e), but is off by about 1%