Answer:
P = 75 W
Explanation:
given,
Distance, L = 8 m
Force,F = 150 N
Time, t = 16 s
Work by the climber
Work done = Force x displacement
W = F. L
W = 150 x 8
W = 1200 J
We know,
P = 75 W
Hence, Power climber is using to climb is equal to 75 W.
Answer:
A and B
Explanation:
Because both of them have only magnitude not direction.
Work done by the force = Force x displacement. Power = work done/time = F.s/t = F.u.t/t = F.u = 95 x 20 = 1900J. {S=ut because acceleration is zero since car is moving at constant velocity}.
Answer:
B
Explanation:
The control is something that is meant to not be changed, the control is a comparison of the experimental.
Answer:
(a) Heat transfer to the environment is: 1 MJ and (b) The efficiency of the engine is: 41.5%
Explanation:
Using the formula that relate heat and work from the thermodynamic theory as:
solving to Q_out we get:
this is the heat out of the cycle or engine, so it will be heat transfer to the environment. The thermal efficiency of a Carnot cycle gives us: 
where T_Low is the lowest cycle temperature and T_High the highest, we need to remember that a Carnot cycle depends only on the absolute temperatures, if you remember the convertion of K=°C+273.15 so T_Low=150+273.15=423.15 K and T_High=450+273.15=723.15K and replacing the values in the equation we get:
