Positive - Friction allows us to create heat in a desperate situation, like being lost in the woods. If we didn't have friction, we would probably freeze to death.
Negative - Friction can also cause unwanted fires, such as forest fires. If friction didn't exist, we wouldn't have these.
I think i used calulater and it gives me 47.5
First, we will get the distance traveled before the driver applied the brakes.
distance = velocity * time
distance = 25*0.34 = 8.5 m
Now, we will calculated the distance that the car traveled after the driver applied the brakes. To do this, we will use the equation of motion:
<span>vf^2 = vi^2 + 2*a*d where:
</span>vf = zero, vi = 25 m/s and a = -7 m/s^2
Note: The negative sign is only to show deceleration
d = <span> 1/2*(625) /(7) = 44.6428 m
The total stopping distance =</span> 8.5 + 44.6428 = 53.1428 m
Answer:
98N and 147N
Explanation:
We have the following information:

We can find the static fricton force as follow,

Where N is the normal force (mg)

Static friction force at 147N is greater than the force applied hence body does not move.
