Answer:

Explanation:
Net force by which man push the lawn mower is given as

now it is given that 37% of this force is vertically downwards
so we will have


now we also know that

here we have


Now work done by this force to move the lawn mower is given as



Answer:
Acceleration due to gravity is 20
So option (E) will be correct answer
Explanation:
We have given length of the pendulum l = 2 m
Time period of the pendulum T = 2 sec
We have to find acceleration due to gravity g
We know that time period of pendulum is given by



Squaring both side


So acceleration due to gravity is 20
So option (E) will be correct answer.
Inertia is directly proportional to mass.
What is Walter Lewin famous for?
Walter Hendrik Gustav Lewin (born January 29, 1936) is a Dutch astrophysicist and former professor of physics at the Massachusetts Institute of Technology.
Lewin earned his doctorate in nuclear physics in 1965 at the Delft University of Technology and was a member of MIT's physics faculty for 43 years beginning in 1966 until his retirement in 2009.
According to Walter Levin,
The concept of moment of inertia is demonstrated by rolling a series of cylinders down an inclined plane.
Inertia is the resistance of any physical object to a change in its velocity. This includes changes to the object's speed, or direction of motion. An aspect of this property is the tendency of objects to keep moving in a straight line at a constant speed when no forces act upon them.
By rolling a series of cylinders down on an inclined plane , he demonstrated that a cylinder have a smooth friction.
He compares the rolling cylinder by using hollow cylinder and a heavy cylinder , and finalize the result that a hollow cylinder moves slowly but the heavy cylinder move faster.
Hence , By doing this experiment he explained about the inertia that Inertia depend on the mass of the object. As the heavy the object it will take more time to travel or move.
Learn more about inertia here:brainly.com/question/3268780
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