The given data is incomplete. The complete question is as follows.
At an accident scene on a level road, investigators measure a car's skid mark to be 84 m long. It was a rainy day and the coefficient of friction was estimated to be 0.36. Use these data to determine the speed of the car when the driver slammed on (and locked) the brakes. (why does the car's mass not matter?)
Explanation:
Let us assume that v is the final velocity and u is the initial velocity of the car. Let s be the skid marks and
be the friction coefficient and m be the mass of car.
Hence, the given data is as follows.
v = 0, s = 84 m,
= 0.36
According to Newton's law of second motion the expression for acceleration is as follows.
F = ma
= ma
= ma
a = 
Also,



= 
= 24.36 m/s
Thus, we can conclude that the speed of the car when the driver slammed on (and locked) the brakes is 24.36 m/s.
Answer:
1923 N
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 65 Kg
Radius (r) = 2.5 m
Velocity (v) = 8.6 m/s
Centripetal force (F) =?
The centripetal force, F, can be obtained by using the following formula:
F = mv²/r
F = 65 × 8.6² / 2.5
F = 65 × 73.96 / 2.5
F = 4807.4 / 2.5
F = 1922.96 ≈ 1923 N
Thus, the magnitude of the centripetal's force acting on the student is approximately 1923 N
Note: if the professor wants the distance between the m = 0 and m = 1 maxima to be 25 cm
Answer:
d = 1.0128×10⁻⁵m
Explanation:
given:
length L = 4.0m
maximum distance between m = 0 and m = 1 , y = 25cm = 0.25m
wavelength λ = 633nm = 633×10⁻⁹m
note:
dsinθ = mλ (constructive interference)
where d is slit seperation, θ is angle of seperation , m is order of interference , and λ is wavelength
for small angle
sinθ ≈ tanθ
mλ


d = 1.0128×10⁻⁵m
Answer: D
Explanation: read the answers above and compare to your test
Answer:
(e)
Explanation:
At resonance we know that 
That is 



We have given resonance frequency f =4511 Hz and inductance L=1.82 mH
So 



So option e is the correct answer