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.
The average acceleration of the cheetah is 7.75 m/s²
The given parameters;
velocity of the cheetah, v = 31 m/s
time of motion, t = 4 seconds
The average acceleration of the cheetah is calculated as follows;

where;
v is the final velocity
u is the initial velocity
t is the time of motion
Assuming the cheetah started from rest, the initial velocity, u = 0
The average acceleration is calculated as follows;

Thus, the average acceleration of the cheetah is 7.75 m/s²
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Answer:

Explanation:
We are given that
|v|=11
|w|=23
|v-w|=30
We have to find the value of |v+w|
|a-b|^2=(a+b)\cdot (a+b)=a^2+b^2-2|a||b|cos\theta
Using the formula






Using the formula




Answer:
D. 100 cm
Explanation:
The speed of a wave is the wavelength times the frequency.
v = λf
Wave A and B have the same speed, so:
λf = λf
(50 cm) (7000 Hz) = λ (3500 Hz)
λ = 100 cm
An VIRTUAL image cannot be projected, and
forms where light rays appear to originate.