Efficiency =
(useful work you get out of it) / (work you put into it)
= (100,000 J) / (250,000 J)
= 0.4 = 40% (choice-A)
4 times more then real
Explanation:
if the radius of the earth decrease by 50% then the acceleration due to gravity increases by 4 times.
D)
Density is equal to mass/volume, so in your case:
density=1.3/1000=0.0013 g/cm^3
a) The velocity of the boat relative to the shore is 3.40 m/s and b) The position of the boat relative to its point of origin after 3s is 10.20m.
Here it is given that the speed of the boat (x) = 2.20m/s
The speed of the stream current (y) = 1.20m/s
a) We have to find the velocity of the boat relative to the shore.
The speed of the boat = x + y
= 2.20 + 1.20
= 3.40m/s
b) Now we have to find the position of the boat after 3s
The formula for speed:
Speed = Distance/ Time
distance = speed × time
speed = 3.40m/s
Time = 3s
distance = 3.40 × 3
= 10.20 m
Therefore we get a) speed as 3.40m/s and b) distance as 10.20m.
To know more about the boat and stream refer to the link given below:
brainly.com/question/382952
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