Answer:
μ = 0.408
Explanation:
given,
speed of the automobile (u)= 20 m/s
distance = 50 m
final velocity (v) = 0 m/s
kinetic friction = ?
we know that,
v² = u² + 2 a s
0 = 20² + 2 × a × 50
a = 4 m/s²
We know
F = ma = μN
ma = μ mg
a = μ g
μ = 0.408
hence, Kinetic friction require to stop the automobile before it hit barrier is 0.408
Answer:
28.1 mph
Explanation:
The force of friction acting on the car provides the centripetal force that keeps the car in circular motion around the curve, so we can write:
(1)
where
is the coefficient of friction
m is the mass of the car
g = 9.8 m/s^2 is the acceleration due to gravity
v is the maximum speed of the car
r is the radius of the trajectory
On the snowy day,
So the radius of the curve is
Now we can use this value and re-arrange again the eq. (1) to find the maximum speed of the car on a sunny day, when . We find:
Answer:
The airplane should release the parcel m before reaching the island
Explanation:
The height of the plane is , and its speed is v=150 m/s
When an object moves horizontally in free air (no friction), the equation for the y measured with respect to ground is
[1]
And the distance X is
x = V.t [2]
Being t the time elapsed since the release of the parcel
If we isolate t from the equation [1] and replace it in equation [2] we get
Using the given values:
x = m