A(n) 685 N man stands in the middle of a
frozen pond of radius 14.6 m. He is unable to get to the other side because of a
lack of friction between his shoes and the
ice. To overcome this difficulty, he throws his
1.3 kg physics textbook horizontally toward
the north shore, at a speed of 5 m/s.
The acceleration of gravity is 9.81 m/s
2
.
How long does it take him to reach the
south shore?
Answer in units of s
To determine how long it takes for the man to reach the south shore, we first need to find the initial horizontal velocity of the man after throwing the textbook. As the man throws the textbook horizontally, there is no vertical force acting on him. Therefore, the initial horizontal velocity of the man will be equal to the horizontal velocity of the textbook, which is 5 m/s.
Next, let's calculate the distance the man needs to cover to reach the south shore of the pond. Since he is in the middle of the pond and wants to reach the opposite shore, the distance he needs to cover is equal to the diameter of the pond, which is 2 times the radius. Therefore, the distance is 2 * 14.6 m = 29.2 m.
Using the formula for calculating time (t) with initial velocity (u) and distance (d) for motion in a straight line:
t = d / u
Substituting the values:
t = 29.2 m / 5 m/s
t = 5.84 seconds
Therefore, it will take the man approximately 5.84 seconds to reach the south shore of the pond.