Answer:
I don't know about these problems at all.
Explanation:
I don't know about physics at all
The floor exerts 20 N of force on the chair
Explanation:
We can answer this question by using Newton's third law, which states that:
<em>"When an object A exerts a force (called action) on an object B, object B exerts an equal and opposite force (called reaction) on object A"</em>
In this problem, we can identify:
- Object A as the chair
- Object B as the floor
This means that the force of 20 N exerted by the chair on the floor is the action, and so the force exerted by the floor on the chair is the reaction. Newton's third law states that these two forces are equal and opposite: therefore, the force exerted by the floor on the chair is also 20 N, but in the opposite direction.
Learn more about Newton's third law:
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264Ns
Explanation:
Given parameters:
Time of the push = 3s
Force of push = 88N
Unknown:
Impulse = ?
Solution:
Impulse is defined as the change in momentum of a body when force acts on it.
Impulse = Force x time
Inputting the parameters:
Impulse = 88 x 3 = 264Ns
Learn more:
Momentum brainly.com/question/9484203
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Answer:
Induced current, I = 18.88 A
Explanation:
It is given that,
Number of turns, N = 78
Radius of the circular coil, r = 34 cm = 0.34 m
Magnetic field changes from 2.4 T to 0.4 T in 2 s.
Resistance of the coil, R = 1.5 ohms
We need to find the magnitude of the induced current in the coil. The induced emf is given by :
Where
is the rate of change of magnetic flux,
And 
Using Ohm's law, 
Induced current, 
I = 18.88 A
So, the magnitude of the induced current in the coil is 18.88 A. Hence, this is the required solution.
Answer:
Explanation:
a ) Thermal efficiency = work output / heat input
= .38 MW / 1 MW = .38
OR 38%
Heat rejected at cold reservoir = heat input - work output
1 MW - .38 MW
= 0.62 MW.
b ) For reversible power output
efficiency = T₂ - T₁ / T₂ ; T₂ is temperature of hot reservoir and T₁ is temperature of cold reservoir.
= 1200 - 300 / 1200 = 900 / 1200
= .75
or 75%
rate at which heat is rejected
= 1 - .75 x 1
= .25 MW .
