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
Velocity = Frequency x Wavelength
= 18 x 13 = 234 mm/s
The answer would be 187.95 kg.m/s.
To get the momentum, all you have to do is multiply the mass of the moving object by the velocity.
p = mv
Where:
P = momentum
m = mass
v = velocity
Not the question is asking what is the total momentum of the football player and uniform. So we need to first get the combined mass of the football player and the uniform.
Mass of football player = 85.0 kg
Mass of the uniform = <u> 4.5 kg</u>
TOTAL MASS 89.5 kg
So now we have the mass. So let us get the momentum of the combined masses.
p = mv
= (89.5kg)(2.1m/s)
= 187.95 kg.m/s
Answer:
(D )
and 
Explanation:
Given that, the rms value of current is 10 ampere and its frequency is 50 Hz.
Now maximum value of current can be calculated as,

The time period is defined as,

Now the time taken by alternating current going from zero to maximum value is,

Therefore, the time taken by alternating current to reach maximum value is
and the peak value of current is
.