Explanation:
Given that,
A student travels 11 m north and then turns around to travel 25 m south.
Total time, t = 12 s
The total distance or the total path covered by the student is equal to 11 m + 25 m = 36 m
Displacement of the student or the shortest path covered is d = 25-11 = 14 m
(a) The student's average speed = total distance/total time
(b) The student's average velocity = total displacement/total time
Explanation:
In order to compute correctly the sum of the two terms, we have to rewrite one of them such that they have the same exponent.
The two terms are:
For instance, we can re-write the second term such as it also has a power 
. In order to do that, we have to move the decimal point one place to the left, therefore:
At this point, the two numbers have the same exponent, so we can just add them together by adding the bases and keeping the same exponent, -2:
Answer:
Time=15,Mass=3,Acceleration due to gravity=10,Height=50,Power=?.
Power=mgh/t.....which is 3×10×50=1500/15=100Watts.
The water in a reservoir behind a hydropower dam is another example of potential energy. The stored energy in the reservoir is converted into kinetic energy (motion) as the water flows down a large pipe called a penstock and spins a turbine.
Hi there!
a)
We can use the equation t = √2d/g to solve. (Let's let g = 10 m/s²)
**How to get this equation**
We have the equation:
Δd = vit + 1/2at²
For freefall, we know that vi = 0, so we are left with:
Δd = 1/2at²
We know that a = g. Rearrange in terms of t:
2Δd / a = t²
Square root both sides:
√(2d/a) = t
Plug in the height and gravity:
t = √2(400)/10 = √800/10 = √80 ≈ 8.94 sec
b)
Find the final speed using the following formula:
vf = √2gd
**How to derive**
We know the equation:
vf² = vi² + 2ad
vi = 0, so:
vf² = 2ad
Square root both sides:
vf = √2ad
vf = √2(400)(10) = √8000 ≈ 89.44 m/s
