Answer:
μk = (Vf - Vc)/(T×g)
Explanation:
Given
Vi = initial velocity of the car
Vf = final velocity of the car
T = Time of application of brakes
g = acceleration due to gravity (known constant)
Let the mass of the car be Mc
Assuming only kinetic frictional force acts on the car as the driver applies the brakes,
The n from Newtown's second law of motion.
Fk = Mc×a
Fk = μk×Mc×g
a = (Vf - Vc)/T
Equating both preceding equation.
μk×Mc×g = Mc × (Vf - Vc)/T
Mc cancels out.
μk = (Vf - Vc)/(T×g)
Answer:
Explanation:
Remark
Let's start with the second question first. If the two forces aren't balanced, the truck will move in some direction. So the downward force of the truck must equal the upward force provided by the pavement pushing up.
Mass of truck = 9500 kg. Remember mass is directionless and it is not a force or weight. That truck would have a mass of 9500 kg anywhere in the universe.
Givens
m = 9500
a = 9.8
Force or weight = ?
Formula and Solution
F = m * a
F = 9500 * 9.8
F = 93100 N
Comment
That force does have a direction. It is down.
The balancing force (you call it the reaction force) going upward is 93100 N
Option D, the sentence that best describes the object is the material of the object can be magnetized.
<h3>Atoms of magnetic material</h3>
The direction of the magnetic fields of the atoms that make up an object is always aligned towards the north pole or south of the material.
Objects that are made of unmagnetised materials such iron, cobalt and nickel are attracted to either pole of a magnet, but not repelled.
The diagram given shows unmagnetised material, and hence the material of the object can be magnetized.
Learn more about magnets here: brainly.com/question/14997726
#SPJ1
