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!
False sometimes you get a bad mutation
Answer:
A. 69.9m
Explanation:
Given parameters:
Initial velocity = 10.5m/s
Final velocity = 21.7m/s
Time = 4.34s
Unknown:
Distance traveled = ?
Solution:
Let us first find the acceleration of the car;
Acceleration = 
v is final velocity
u is initial velocity
t is the time
Acceleration = 
= 2.58m/s²
Distance traveled;
V² = U² + 2aS
21.7² = 10.5² + 2 x 2.58 x S
360.64 = 2 x 2.58 x S
S = 69.9m
Answer:
v = 4.18 m/s
Explanation:
given,
frequency of the alarm = 872.10 Hz
after passing car frequency she hear = 851.10 Hz
Speed of sound = 343 m/s
speed of the jogger = ?
speed of the
v_o = 872.1 - 10.5
The speed of jogger
v = 4.18 m/s
= Heat released to cold reservoir
= Heat released to hot reservoir
= maximum amount of work
= temperature of cold reservoir
= temperature of hot reservoir
we know that
eq-1
maximum work is given as
= -
using eq-1
= 
-
