A fuel cell combines hydrogen and oxygen to produce electricity, heat, and water. Fuel cells are often compared to batteries. Both convert the energy produced by a chemical reaction into usable electric power.
Answer:
The ratio of the power generated by the engines are 
(b) is correct option.
Explanation:
Given that,
Mass of Tesla = 2000 Kg
Torque = 400 Nm
Mass of Mercedes = 1.5 M Tesla
The Benz engine produces 50% more torque than the Tesla.
We need to calculate the power generated by the engines 6 seconds after a start from rest
Using formula of power
We know that,
Put the value of F and v in equation (I)
Here, r and t are same for both bodies.
We need to calculate the ratio of the power generated by the engines
Using formula of power
Put the value into the formula
Hence, The ratio of the power generated by the engines are
I don't personally know the answer, but this article should help!
http://www.nasa.gov/audience/forstudents/5-8/features/nasa-knows/what-is-a-black-hole-58.html
Answer:
F = 4856.32 N
Explanation:
Given,
A satellite is orbiting earth at a distance from Earth surface, h = 35000 m
The mass of the satellite, m = 500 Kg
The radius of the Earth, R = 6.371 x 10⁶ m
The mass of the Earth, M = 5.972 x 10²⁴ Kg
The gravitational constant, G = 6.67408 x 10 ⁻¹¹ m³ kg⁻¹ s⁻²
The force between the Earth and the satellite is given by the formula
F = GMm/(R+h)² N
Substituting the values in the above equation
F = (6.67408 x 10 ⁻¹¹ X 5.972 x 10²⁴ X 500) / (6.371 x 10⁶ + 35000)²
= 4856.32 N
Hence, the force between the planet and the satellite is, F = 4856.32 N
The answer is #3: Oxidation because oxidation is when a substance reacts with oxygen, which causes the substance to rust. When a rock contains iron and that iron comes in contact with oxygen, iron oxide is created; this weakens the rock.
