Answer:
Explanation:
mass of refrigerator, m = 110 kg
coefficient of static friction, μs = 0.85
coefficient of kinetic friction, μk = 0.59
(a) the minimum force required to just start the motion in refrigerator
F = μs x mg
F = 0.85 x 110 x 9.8
F = 916.3 N
(b) The force required to move the refrigerator with constant speed
F' = μk x mg
F' = 0.59 x 110 x 9.8
F' = 636.02 N
(c) Let a be the acceleration.
Net force = Applied force - friction force
F net = 950 - 636.02
F net = 313.98 N
a = F net / mass
a = 313.98 / 110
a = 2.85 m/s²
Force can be exerted into an object with out it moving, but if you were to move the object due to force it would be considered work. (yes, you can exert force without having the object moving)
To solve this problem we will apply the concepts related to the Doppler effect. The Doppler effect is the change in the perceived frequency of any wave movement when the emitter, or focus of waves, and the receiver, or observer, move relative to each other. Mathematically it can be described as

Here,
=frequency received by detector
=frequency of wave emitted by source
=velocity of detector
=velocity of source
v=velocity of sound wave
Replacing we have that,


Therefore the frequencty that will hear the passengers is 422Hz
Answer:
3.28 cm
Explanation:
To solve this problem, you need to know that a magnetic field B perpendicular to the movement of a proton that moves at a velocity v will cause a Force F experimented by the particle that is orthogonal to both the velocity and the magnetic Field. When a particle experiments a Force orthogonal to its velocity, the path it will follow will be circular. The radius of said circle can be calculated using the expression:
r = 
Where m is the mass of the particle, v is its velocity, q is its charge and B is the magnitude of the magnetic field.
The mass and charge of a proton are:
m = 1.67 * 10^-27 kg
q = 1.6 * 10^-19 C
So, we get that the radius r will be:
r =
= 0.0328 m, or 3.28 cm.
Answer:
A) and B) are correct.
Explanation:
Let's take a look at the attached picture. Now
The total voltage across both capacitors is the same as the sum of the voltage from each device, that statement is true for any electrical device connected in series. So a) is TRUE
The equivalent capacitance is going to be: 
And that value can be mathematically proven that is always less than any of the values of each capacitor. So b is TRUE
And through both capacitors flow the same current, but the amount of charge depends on the value of the capacitors, so only could be the same if the capacitors are the same value. Otherwise, don't. C) not always, so FALSE