Explanation:
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Answer:
mu = 0.56
Explanation:
The friction force is calculated by taking into account the deceleration of the car in 25m. This can be calculated by using the following formula:

v: final speed = 0m/s (the car stops)
v_o: initial speed in the interval of interest = 60km/h
= 60(1000m)/(3600s) = 16.66m/s
x: distance = 25m
BY doing a the subject of the formula and replace the values of v, v_o and x you obtain:

with this value of a you calculate the friction force that makes this deceleration over the car. By using the Newton second's Law you obtain:

Furthermore, you use the relation between the friction force and the friction coefficient:

hence, the friction coefficient is 0.56
Answer:
The friction force is 250 N
Explanation:
The desk is moving at constant velocity. This means that its acceleration is zero: a = 0. Newton's second law states that the resultant of the forces acting on the desk is equal to the product between mass (m) and acceleration (a):

In this case, we know that the acceleration is zero: a = 0, so also the resultant of the forces must be zero:
(1)
We are only interested in the forces acting along the horizontal direction, since it is the direction of motion. There are two forces acting in this direction:
- the pull, forward, F = 250 N
- the friction force, backward, 
Given (1), we have

So the force of friction must be equal to the pull:

Answer:
The right shoe
Explanation:
Both shoes have the same speed.
Answer:
wave number = 0.3348 * 10⁻⁸ cm⁻¹
Explanation:
Given data:
K = 4.808 * 10^2 N/m
<u>Determine the wave number for the infrared absorption</u>
considering vibrational Spectre
k' = 2n / λ ---- ( 1 )
λ = c / v ----- ( 2 )
v = √k / u --- ( 3 )
where : k' = wave number, λ = wavelength, c = velocity of light, v = frequency, k = force constant, u = reduced mass
u = 1.90415 for D35Cl
Input equations 2 and 3 into equation 1 to get the final equation
K' = 2n/c * √k / u
= ( 2 * 3.14 ) / 2.98 * 10^8 ] * (√ 4.808 * 10^2 / 1.90415 )
= 33.486 * 10⁻⁸ m⁻¹ ≈ 0.3348 * 10⁻⁸ cm⁻¹