Hey! I empathize with you, as I just started the energy unit in physics as well!
Alright, lets list what we know, and which equation(s) we need.
PE = Gravitational Potential Energy
m = mass
g = gravity (9.8 m/s^2)
h = height
Guess what?
We need to find the height!
Lets make this more organized:
Known:
m = 40 kg
PE = 14000
g = 9.8 m/s^2
Unknown:
h = ?
================================
Now, if we take a look at the equation PEg = mgh, you will see that we have everything besides the height! So lets solve for the height by substituting in for the variables we know:
14000 J = 40 kg * (9.8 m/s^2) * h
40 * 9.8 = 392
14000 J = 392 * h
14000/392 = h
35.71 m = h
There we go! If you simply list what you know and don't know, you will find the equation you need to solve the problem.
Have a great day and good luck!
Answer:
a) 17.086m
b) 0.1671 m
Explanation:
Given data: speed of water through the hose = 1.81 m/s
through the nozzle = 18.3 m/s
We know that maximum height of an object with upward velocity v is given by,
a) H = v^2/2g
where H is the maximum height water emerges
= 18.3^2/(2×9.8) = 17.086 m answer
b) Again,
H = v^2/2g
= 1.81^2/(2×9.8) = 0.1671 m
250/4= 62.5 mph
to find the mph of a car, you need to divide the number of miles traveled by the hours that it took to travel that many miles
The train’s average speed is 80km/h
Answer:
1923 N
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 65 Kg
Radius (r) = 2.5 m
Velocity (v) = 8.6 m/s
Centripetal force (F) =?
The centripetal force, F, can be obtained by using the following formula:
F = mv²/r
F = 65 × 8.6² / 2.5
F = 65 × 73.96 / 2.5
F = 4807.4 / 2.5
F = 1922.96 ≈ 1923 N
Thus, the magnitude of the centripetal's force acting on the student is approximately 1923 N
