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3 years ago

PLEASE REAL ANSWERS IM SUPER BEHIND

Physics

1 answer:

natima [27]3 years ago

8 0

Answer:

25000W

Explanation:

Kinetic Energy, EK=(1/2)mv2. Energy is conserved, so the work done by the brakes, W, must be equal to the change in kinetic energy of the car, ∆EK. Therefore: W = ∆EK = (1/2)1000(152-52) = 0.51000200 = 100000 = 1*105J. Since power P = W/T, the average power output of the brakes is equal to the total work done by the brakes over the time that the brakes are applied for, therefore: P = 100000/4 = 25000W.

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50 points if brainliest !!!!!!!!!!

Natasha_Volkova [10]

Answer:

$weight = mg \\ = 70 \times 10 \\ = 700 \: newtons$

$force = 700 \: newtons$

$force = mass \times acceleration \\ 700 = 70 \times a \\ a = 10 \: {ms}^{ - 2}$

4 0

3 years ago

Two concentric current loops lie in the same plane. The smaller loop has a radius of 3.4 cmcm and a current of 12 AA. The bigger

Free_Kalibri [48]

Answer:

Explanation:

Given that,

Current in loops are

i1 = 12A

i2 = 20A

The loops are 3.4cm apart

The magnetic field at the center is found to be zero, so when want to find the radius of bigger loop

Magnetic Field is given as

B= μoi/2πr

Where,

μo is a constant = 4π×10^-7 Tm/A

r is the distance between the two wires

i is the current in the wires

B is the magnetic field

NOTE

Field due to large loop should be equal to the smaller loop.

B1 = B2

μo•i1 / 2π•r1 = μo•i2 / 2π•r2

Then, μo, 2π cancels out, so we have

i1 / r1 = i2 / r2

Make r2 subject of formula

i1•r2 = i2•r1

r2 = i2•r1 / i2

r2 = 20×3.4/12

r2 = 5.67cm

The radius of the bigger loop is 5.67cm.

4 0

3 years ago

How does the law of conservation of energy apply to machinesBased on the law of conservation of energy, how can we reasonably im

SIZIF [17.4K]

Answer:

According,to the law of conservation of energy,the amount of energy in a closed system always stay constant. ... So,the amount of work output and other transformed energy is equal to the amount of energy inputs. • In this way,the conservation of energy is fulfilled by the machines.

8 0

3 years ago

Please select the word from the list that best fits the definition

enyata [817]

Answer:

conductor

Does not easily transfer electricity

8 0

3 years ago

When water waves meet, they can combine to form new waves. In constructive waves, a ________ amplitude wave is formed. In destru

Sever21 [200]

Answer:

In constructive waves, a greater amplitude wave is formed. In destructive waves, a wave with a smaller amplitude is formed. (option A)

Explanation:

Interference is called the superposition or sum of two or more waves. Depending mainly on the wavelengths, amplitudes and the relative distance between them, there are two types of interference: constructive or destructive.

Constructive interference occurs when there are two waves of identical or similar frequency (both have motions equal to an even number of similar wavelengths) and overlap the peak of one with the peak of the other. These effects add together and make a wave of greater amplitude. All of this is possible because the waves were in the same phase in the beginning (in the same position).

Destructive interference occurs in the opposite case to constructive. When the crest of one wave overlaps the valley of the other, they cancel out since they are in different phases when they overlap (they were in different positions). That is, as in the case of constructive waves they were added, in the case of destructive waves they cancel out (subtract).

So, In constructive waves, a greater amplitude wave is formed. In destructive waves, a wave with a smaller amplitude is formed.

3 0

3 years ago