Question

Three small identical masses are released simultaneously from the top of three inclines. (See tiny url)

//img.homeworklib.com/questions/e752e3f0-baf0-11ea-b6d0-f9c6d1a2e136.png

The three inclines have the same height and they are all frictionless, but they have different angles.

Which object will finish the race first?

A. All three objects will finish at the same time.

B. Object #3 will finish first.

C. Object #1 will finish first.

D. Object #2 will finish first.

Answer 1

Ans..(c) object 1 will reach first...

we know that

In the absence of friction and other forces (tension, applied, etc.), the acceleration of an object on an incline is the value of the parallel component (m*g*sine of angle) divided by the mass (m). This yields the equation

$a=g \sin \Theta$

As the angle increases, the component of force parallel to the incline increases and the component of force perpendicular to the incline decreases. It is the parallel component of the weight vector that causes the acceleration. Thus, accelerations are greater at greater angles of incline. so in Fig 1,2,3 the inclined angle of1 is greater than 2 and 2 is grater than 3. As acceleration is more the body moves fast reaches first.

So Fig 1 body will reach first.