125,152 views
36 votes
36 votes
8.

A
2.0 m
A 1.0 kg box slides without friction around the
loop-the-loop apparatus as shown in the
diagram. If the object starts from rest at point A,
and the radius of the loop is 0.75 m, what is the
speed of the box at point B?

User Mladen Uzelac
by
2.4k points

1 Answer

21 votes
21 votes

Answer:

6.26 m/s

Step-by-step explanation:

From the given information:

Using the conservation of Energy;

M.E at A =M.E at B


(1)/(2)mv_A^2 + mgh _A = (1)/(2)mv_B^2 + mgh_B

Replacing the values given in the equation:


(1) (9.8) (2 \ m) +(1)/(2)(0)^2 = 1 * 9.8 * 0 + (1)/(2)(1) * v_B^2 \\\\ 19.6 + 0 = 0 + 0.5v_B^2\\ \\ v_B^2 = (19.6)/(0.5) \\ \\ v_B^2 = 39,2 \\ \\ v_B = √(39.2) \\ \\ \mathbf{v_B = 6.26 \ m/s}

User Ben Companjen
by
3.3k points