Answer:
4.42 x 10⁷ W/m²
Explanation:
A = energy absorbed = 500 J
η = efficiency = 0.90
E = Total energy
Total energy is given as
E = A/η
E = 500/0.90
E = 555.55 J
t = time = 4.00 s
Power of the beam is given as
P = E /t
P = 555.55/4.00
P = 138.88 Watt
d = diameter of the circular spot = 2.00 mm = 2 x 10⁻³ m
Area of the circular spot is given as
A = (0.25) πd²
A = (0.25) (3.14) (2 x 10⁻³)²
A = 3.14 x 10⁻⁶ m²
Intensity of the beam is given as
I = P /A
I = 138.88 / (3.14 x 10⁻⁶)
I = 4.42 x 10⁷ W/m²
Answer: 117.60N
Explanation:
Weight is a force. Therefore, we can use the force formula to find weight.

W = weight
m = mass
g = acceleration due to gravity (
)

Answer:
A. a material burns out when current is excessive
Answer:
16
Explanation:
Mechanical advantage = force out / force in
MA = 2000 N / 125 N
MA = 16
You are sitting at the center of a large turntable at an amusement park as it is set spinning freely. You decide to crawl towards the edge of the turntable. Rotational speed will decrease
There is no external torque
hence , the angular momentum of the table is conserved
L (initial) = L ( final)
since , L = m*v*r
where
m = mass
v = velocity
r = radius
If the person is crawled towards the outer rim, then the rotational inertia of the turntable will increase. In order to conserve the angular momentum , its rotational speed will decrease as mass and radius cannot be altered .
To learn more about torque here :
brainly.com/question/19104073
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