Answer:
-4.0 N
Explanation:
Since the force of friction is the only force acting on the box, according to Newton's second law its magnitude must be equal to the product between mass (m) and acceleration (a):
(1)
We can find the mass of the box from its weight: in fact, since the weight is W = 50.0 N, its mass will be

And we can fidn the acceleration by using the formula:

where
v = 0 is the final velocity
u = 1.75 m/s is the initial velocity
t = 2.25 s is the time the box needs to stop
Substituting, we find

(the acceleration is negative since it is opposite to the motion, so it is a deceleration)
Therefore, substituting into eq.(1) we find the force of friction:

Where the negative sign means the direction of the force is opposite to the motion of the box.
In a way it’s true because you can get a ticket for getting caught littering
D. It must be able to be magnetized
Explanation:
The requirement for a core to be used in an electromagnet is that it must be able to be magnetized.
An electromagnet is a type of magnet produced by electricity.
- They typically run and produce magnetic fields in the vicinity of electrical currents.
- These magnets are not permanent magnets.
- When the electrical current is removed, the magnetic property of the substance is lost.
- The core of an electromagnet is usually made up of a material that can easily be magnetized in the presence of magnetic fields.
- Some of the materials used are cobalt, iron, nickel.
learn more:
Electromagnet brainly.com/question/2191993
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She hung up the pieces of cotton BEFORE putting the fan on, also the water evaporating can take longer or shorter even if they are all the same :))
A bowling ball of 7.0 kg will be weighed around 15.54 lbs (pounds) at the surface of the Earth.
<u>Explanation:</u>
The weight of the bowling ball as given in the question,

Since we know that the force of gravity acting on an object at the surface of the Earth is 2.22 lb i.e. the object will be weighed as 2.22 lb at the surface of the Earth. Similarly, here in this case;
The weight of the bowling ball,


Hence, the bowling ball will be weighed as 15.54 lbs at the surface of the Earth.