The first thing you should know to answer this question is the following conversion:
1mi = 5280feet
We have then that the speed is:
v = ((1/4) * (5280)) / (8.96)
v = 147.32 feet / s
Answer:
the car's velocity (in ft / s) at the finish line is 147.32 feet / s
Answer:
In terms of distance, average speed is 20 km/h
In terms of displacement, average speed is 0 km/h.
Explanation:
Total distance:

Total time is 3.0 hours
but:

In terms of distance.
substitute:


In terms of displacement:

To solve this problem it is necessary to apply the concepts related to Normal Force, frictional force, kinematic equations of motion and Newton's second law.
From the kinematic equations of motion we know that the relationship of acceleration, velocity and distance is given by

Where,
Final velocity
Initial Velocity
a = Acceleration
x = Displacement
Acceleration can be expressed in terms of the drag coefficient by means of
Frictional Force
Force by Newton's second Law
Where,
m = mass
a= acceleration
Kinetic frictional coefficient
g = Gravity
Equating both equation we have that



Therefore,


Re-arrange to find x,

The distance traveled by the car depends on the coefficient of kinetic friction, acceleration due to gravity and initial velocity, therefore the three cars will stop at the same distance.
Answer:
option C (1 and 4)
Explanation:
Like poles repel each other, unlike poles attract each other
' +4 m/s² ' means that the pigeon's speed is 4 m/s greater every second.
Starting from zero speed, after 10 seconds, its speed is
(10 x 4m/s) = 40 m/s.
We can't say anything about its velocity, because we have
no information regarding the direction of its flight.