Answer:
The shortest distance in which you can stop the automobile by locking the brakes is 53.64 m
Explanation:
Given;
coefficient of kinetic friction, μ = 0.84
speed of the automobile, u = 29.0 m/s
To determine the the shortest distance in which you can stop an automobile by locking the brakes, we apply the following equation;
v² = u² + 2ax
where;
v is the final velocity
u is the initial velocity
a is the acceleration
x is the shortest distance
First we determine a;
From Newton's second law of motion
∑F = ma
F is the kinetic friction that opposes the motion of the car
-Fk = ma
but, -Fk = -μN
-μN = ma
-μmg = ma
-μg = a
- 0.8 x 9.8 = a
-7.84 m/s² = a
Now, substitute in the value of a in the equation above
v² = u² + 2ax
when the automobile stops, the final velocity, v = 0
0 = 29² + 2(-7.84)x
0 = 841 - 15.68x
15.68x = 841
x = 841 / 15.68
x = 53.64 m
Thus, the shortest distance in which you can stop the automobile by locking the brakes is 53.64 m
Answer:
The answer to your question is when time = 50 s, work = 5000 J
when time = 90 s, work = 9000 J
Explanation:
Data
time = 50 s or 90 s
Power = 100 watts
Power is defined as the rate of work done per unit of time.
Power = Work / time
-Solve for Work
Work = Power x time
-Substitution
Work = 100 x 50
-Result
Work = 5000
2.-When time = 90 s
Work = 100 x 90
-Result
Work = 9000 watts
Rocks and sediments I believe