Hello!
Work is equal to negative change in PE and PE=mgh and Power is change in work/change in time
So we have
56.1kg * 9.80m/s^2 * 16m = 8796.5 J of PE at top of run and -8796.5J of work done also
if it takes him 12s then we need to find the time gravity alone would bring him to the bottom. we get
16m=1/2at^2 and solving for t we get
t=sqrt(32/9.80m/s^2)=1.81s
so the difference in time is 12-1.8=11.2s
now we can find avg power=work/time = 8796.5J/11.2s = 785W or 785J/s
Hope this helps! Any questions please ask! Thank you!
Answer:
(a) -8064 N
(b) 8064 N
Explanation:
(a)
From Newton’s law of motion, Force, F=ma where m is mass and a is acceleration.
Since acceleration is the rate of change of velocity per unit time, then where v is velocity and the subscripts f and I denote final and initial
For the first ball, the mass is 0.28 Kg, final velocity is zero since it finally comes to rest, t is 0.00025 s and initial velocity is given as 7.2 s. Substituting these values we obtain
(b)
For the second ball, the mass is also 0.28 Kg but its initial velocity is taken as zero, the final velocity of the second ball will be equal to the initial velocity of the second ball, that is 7.2 m/s and the time is also same, 0.00025 s. By substitution
Here, we prove that action and reaction are equal and opposite
True, scientists often talk to each other to figure out if their results were similar and what they could have done better.
Although, talking to other scientists does have risks, other scientists could copy your work and further better it.
So, your final answer is TRUE, sorry for the long answer, I needed to have a word count about 20 characters and then I got carried away! lol
Answer:
they were slaves, so they did practically everything anyone didn't do.
Explanation:
btw, which war? or battle?
