Answer:
2.2N
Explanation:
Given parameters:
Work done = 379.5J
Height = 173m
Unknown:
Amount of force exerted on the sled = ?
Solution:
The amount of force she exerted on the sled is the same as her weight.
Work done is the force applied to move a body through a distance.
Work done = mgh
m is the mass
g is the acceleration due to gravity
h is the height
mg = weight;
Work done = weight x h
379.5 = weight x 173
weight = = 2.2N
Aaron's car is moving at speed of 30 m/s
His reaction time is given as 0.7 s
but when he is tired the reaction time is doubled
Now we need to find the distance covered by his car when he is tired during the time when he react to apply brakes
So here since during this time speed is given as constant so we can say that distance covered can be product of speed and time
So here we can use
So the car will move to 42 m during the time when he apply brakes