Answer:
t = 2 hours
Explanation:
Given that,
Distance of the town, d = 90 miles
Speed, v = 45 mph
We need to find the time to get there. The speed of an object is given by :
Where
t is time
So, the required time is 2 hours.
Answer: C)The yellow car was faster. Yellow traveled at a speed of 50 mph while green was traveling at an average of 40 mph.
Explanation:
The speed of each car is defined as:
where d is the distance traveled by the car and t is the time taken.
For the yellow car, d=400 mi and t=8 h, so its speed is
For the green car, d=400 mi and t=10 h, so its speed is
So, the correct choice is
C)The yellow car was faster. Yellow traveled at a speed of 50 mph while green was traveling at an average of 40 mph.
I would say the plastic grip because glass, wood, and plastic are all good conductors of electricity
It will be unaffected by the magnet because it has no magnetic field. If you were to maybe have electricity going through it is the only way it would have anything to do with the magnet.
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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
