Answer:
The net force = 0
Explanation:
The given information includes;
The mass of the crate = 250 kg
The way the helicopter lifts the crate = Uniformly (constant rate (speed), no acceleration)
In order to pull the crate upwards, the helicopter has to provide a force equivalent to the weight of the crate keeping the helicopter on the ground.
The weight of the crate = The mass of the crate × The acceleration due gravity acting on the crate
The weight of the crate, 
↓ = 250 kg × 9.81 m/s² = 2,452.5 N
The force the helicopter should provide to just lift the crate, 
↑ = The weight of the crate = 2,452.5 N
The net force, 
= ↑ - ↓ = 2,452.5 N - 2,452.5 N = 0
The net force = 0.
Answer: Yes
Air serves as a propagation medium.
Explanation:
Propagation of sound wave require a medium for transmission. Sound is produced by vibrating objects, The matter or substance through which sound is transmitted is called a medium. It can be solid, liquid or gas. Therefore to propagate sounds (human voice) from one end of a lecture hall to the other we need a propagation medium which is air. Air serves as a propagation medium.
A battery-operated car moves forward as a result of which device?
A) Electromagnet
B) Generator
<u>C) Motor </u>
D) Transformer
Answer:
This shows inertia because inertia is an object's resistance to change in motion. When the person (imma call them a she) who pulled the chair from under the guy did that, the chair was the one affected by the force of the girl, not the guy. The guy continued heading in the direction he was originally going, which was down.
At least, that's about how I would answer this question.
