Answer:
I believe its a and c but my notes are all kinds of messed up so im sorry if its wrong
Explanation:
Answer:
352,088.37888Joules
Explanation:
Complete question;
A hiker of mass 53 kg is going to climb a mountain with elevation 2,574 ft.
A) If the hiker starts climbing at an elevation of 350 ft., what will their change in gravitational potential energy be, in joules, once they reach the top? (Assume the zero of gravitational potential is at sea level)
Chane in potential energy is expressed as;
ΔGPH = mgΔH
m is the mass of the hiker
g is the acceleration due to gravity;
ΔH is the change in height
Given
m = 53kg
g = 9.8m/s²
ΔH = 2574-350 = 2224ft
since 1ft = 0.3048m
2224ft = (2224*0.3048)m = 677.8752m
Required
Gravitational potential energy
Substitute the values into the formula;
ΔGPH = mgΔH
ΔGPH = 53(9.8)(677.8752)
ΔGPH = 352,088.37888Joules
Hence the gravitational potential energy is 352,088.37888Joules
Q = mass water x specific heat water x delta T.
<span>714,000 = mass water x specific heat water x 30.
Substitute specific heat water and solve for mass water.</span>
Answer:
power, P = 90 hp
Explanation:
It is given that,
Mass of the car, m = 1500 kg
Initial velocity of car, u = 0
Final velocity of car, v = 25 m/s
Time taken, t = 7 s
We need to find the average power delivered by the engine. Work done divided by total time taken is called power delivered by the engine. It is given by :

According to work- energy theorem, the change in kinetic energy of the energy is equal to work done i.e.


P = 66964.28 watts
Since, 1 hp = 746 W
So, P = 89.76 hp
or
P = 90 hp
So, the average power delivered by the engine is 90 hp. Hence, the correct option is (E) " 90 hp".