Which of the following statements about the conservation of momentum is not correct? Momentum is conserved for a system of objec
1 answer:
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Answer:
6.0 × W/
Explanation:
From Wien's displacement formula;
Q = e A
Where: Q is the quantity of heat transferred, e is the emissivity of the surface, A is the area, and T is the temperature.
The emissive intensity = = e
Given from the question that: e = 0.6 and T = 1000K, thus;
emissive intensity = 0.6 ×
= 0.6 × 1.0 ×
= 6.0 ×
Therefore, the emissive intensity coming out of the surface is 6.0 × W/
.
The given data is incomplete. The complete question is as follows.
At an accident scene on a level road, investigators measure a car's skid mark to be 84 m long. It was a rainy day and the coefficient of friction was estimated to be 0.36. Use these data to determine the speed of the car when the driver slammed on (and locked) the brakes. (why does the car's mass not matter?)
Explanation:
Let us assume that v is the final velocity and u is the initial velocity of the car. Let s be the skid marks and be the friction coefficient and m be the mass of car.
Hence, the given data is as follows.
v = 0, s = 84 m, = 0.36
According to Newton's law of second motion the expression for acceleration is as follows.
F = ma
= ma
= ma
a =
Also,
=
= 24.36 m/s
Thus, we can conclude that the speed of the car when the driver slammed on (and locked) the brakes is 24.36 m/s.
Answer:
Explanation:
Given data
Electromagnetic waves from the sun is I=1.4kW/m² at 80%
Area a=(0.30×0.51)m²
Time t=1.30 hr
To find
Energy E
Solution
The energy received by your back is calculated as: