Two people are having a race pushing equal sized boxes up a hill. joe pushes the box up the hill in 10 seconds and cindy pushes
1 answer:
You might be interested in
Answer:
-10 N, not balanced
Explanation:
Force is a vector quantity, so in order to find the net force on an object, we must use vector addition rule.
This means that if two forces acting on an object along the same line, we have to choose one direction as positive, and write the two forces with the correct sign.
In this problem, we have two forces acting along a line on the car:
- A first force of
- A second force of
Therefore, the net force on the car is:
Moreover, the net force on an object is said to be "balanced" if it is zero: in this case, it is not zero, so it is not balanced.
Answer:
Time, t = 0.23 seconds
Explanation:
It is given that,
Initial speed of the ranger, u = 52 km/h = 14.44 m/s
Final speed of the ranger, v = 0 (as brakes are applied)
Acceleration of the ranger,
Distance between deer and the vehicle, d = 87 m
Let d' is the distance covered by the deer so that it comes top rest. So,
d' = 26.06 m
Distance between the point where the deer stops and the vehicle is :
D=d-d'
D=87 - 26.06 = 60.94 m
Let t is the maximum reaction time allowed if the ranger is to avoid hitting the deer. It can be calculated as :
t = 0.23 seconds
Hence, this is the required solution.
Answer: 3.49 s
Explanation:
We can solve this problem with the following equation of motion:
(1)
Where:
is the final height of the ball
is the initial height of the ball
is the initial velocity (the ball was dropped)
is the acceleratio due gravity
is the time
Isolating :
(2)
(3)
Finally we find the time the ball is in the air:
(4)