<span>The true brightness of an object
is called its luminosity. It is the total amount of energy emitted by bright or
meteorological objects over a period of time. It has the SI unit of joules per
second or watts. So the answer is letter A. Intensity is the measure of how
strong the substance or object is when it projects something. Magnitude is a
measure of how great is the size the object produces. Viscosity is the measure
of flow of a substance.</span>
Answer:
W = 30 J
Explanation:
given,
Work done = 10 J
Stretch of spring, x = 0.1 m
We know,
dW = F .dx
we know, F = k x


![W = k[\dfrac{x^2}{2}]_0^{0.1}](https://tex.z-dn.net/?f=W%20%3D%20k%5B%5Cdfrac%7Bx%5E2%7D%7B2%7D%5D_0%5E%7B0.1%7D)

k = 2000
now, calculating Work done by the spring when it stretched to 0.2 m from 0.1 m.

![W = 2000 [\dfrac{x^2}{2}]_{0.1}^{0.2} dx](https://tex.z-dn.net/?f=W%20%3D%202000%20%5B%5Cdfrac%7Bx%5E2%7D%7B2%7D%5D_%7B0.1%7D%5E%7B0.2%7D%20dx)
W = 1000 x 0.03
W = 30 J
Hence, work done is equal to 30 J.
Answer:
W = 8.92 10² kJ
Explanation:
For this exercise they give us the strength, we must calculate the distance traveled, for this we need the rocket acceleration let's use Newton's second law
F = m a
a = F / m
a = 20 103/1400
a = 14.29 m/s²
With kinematics we can find the distance traveled
² = v₀² + 2 a x
x = (
²-v₀²) / 2 a
x = (50² -35²) / 2 14.29
x = 1275 / 28.58
x = 44.61 m
Let's calculate the work
W = F.d
The bold is vector; as indicated by the force is in the direction of movement the scalar product is reduced to the ordinary product
W = F d
W = 20 10³ 44.61
W = 8.92 10⁵ J
W = 8.92 10² kJ
im pretty sure it was tennis
Hey!
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Formula:
speed = distance ÷ time
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Solution:
Distance is 60 meters.
Time is 60 seconds.
speed = 60 / 60
speed = 1 meters/seconds
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Answer:
1 meters/seconds.
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Hope This Helped! Good Luck!