Answer:
Option ( B ) is correct .
Explanation:
To lift a heavy weight , inclined plane is used . Use of inclined plane , makes the task easier because instead of force mg , force mg sinθ is to be used which is less than mg . Here θ is inclination of inclined plane.
If h be the height by which weight is to be lifted
potential energy acquired by weight = mgh
work done by force mg sinθ = mgsinθ x d where d is displacement required .
mg sinθ x d = mgh ( work done by force = potential energy stored in luggage )
d = h / sinθ
d will be more than h
Hence inclined plane increases the distance to be covered by force applied though it decreases the force itself.
Hence option ( B ) is correct .
The total distance traveled by the body is the sum of the distance it traveled for the first five seconds which is 10 m and that of the next five seconds which is 30 meters. Thus, the total distance traveled is 40 m. Dividing this by the time, will give the average speed. The average speed is therefore, 4 m/s. The answer is letter C.
Answer:
151.2 m/s
Explanation:
m1 = 0.020 kg
m2 = 2.5 kg
vf = 1.2 m/s
m1v1 +m2v2 = (m1 +m2)vf
0.020v1 + 0 = (0.020 +2.5)(1.2)
---> 151.2 m/s
Answer: A.
series or parallel
Explanation:
Total resistance across any branch of a circuit can be found by analyzing whether the branch is connected in series or parallel.
The resistors are connected either in series or parallel. Therefore, the resistance of resistors across a circle can be calculated in series and parallel.
