Answer:
when one organism benefits but harms the other
You can find the mass of an atom by adding the number of protons and neutrons. In this case the atom has 2 protons and 3 neutrons so the mass is 5.
Answer:
13.41 horsepower
Explanation:
Power: This can be defined as the rate at which energy is used up by a body. The S.I unit of power is Watt (W).
The expression for power is given as,
P = Ek/t...................... Equation 1
Where P = power, Ek = Kinetic Energy of the car, t = time.
Recall that,
Ek = 1/2mΔv²............ Equation 2
Where m = mass of the car, Δv = change in velocity of the car.
Substitute equation 2 into equation 1
P = 1/2(mΔv²)/t...................... Equation 3
Given:m = 1000 kg, Δv = 30-20 = 10 m/s, t = 5 s
Substitute into equation 3
P = 1/2(1000×10²)/5
P = 10000 W.
If,
745.7 W = 1 hp,
Then,
10000 W = (10000/745.7) hp
= 13.41 hp.
P = 13.41 horsepower
Answer:
1) The block of wood is at rest.
2) Weight and Normal Reaction (see attached diagram).
Explanation:
<u>Assumptions</u>
- The block of wood is a particle (a body whose mass acts at a point, so its dimensions don't matter).
- There are no other external forces involved.
<u>Question 1</u>
"At rest" or "resting" means that the <u>object isn't moving</u>.
Therefore, the block of wood is at rest.
<u>Question 2</u>
Forces that are acting on the block of wood:
- <u>Weight (W)</u>: Due to the particle's mass, m, and the acceleration due to gravity, g: W = mg
(Weight always acts downwards).
- <u>Normal Reaction (R or N)</u>: The reaction from a surface.
(Normal Reaction is always at 90° to the surface).
See attached diagram.