Answer:
the intensity will be 4 times that of the earth.
Explanation:
let us assume the following:
intensity of light on earth =J
distance of earth from sun = d
intensity of light on other planet = K
distance of other planet from sun = 
(from the question, the planet is half as far from the sun as earth)
from the question the intensity is inversely proportional to the square of the distance, hence
- intensity on earth : J =
J
= 1 ... equation 1
- intensity on other planet : K =
(the planet is half as far from the sun as earth)
K
= 1 ....equation 2
- equating both equation 1 and 2 we have
J = K
J = K
J = 
K = 4J
intensity of light on other planet (K) = 4 times intensity of light on earth (J)
Answer:
A sloping surface separating air masses that differ in temperature and moisture content is called a front.
Apply conservation of angular momentum:
L = Iw = const.
L = angular momentum, I = moment of inertia, w = angular velocity, L must stay constant.
L must stay the same before and after the professor brings the dumbbells closer to himself.
His initial angular velocity is 2π radians divided by 2.0 seconds, or π rad/s. His initial moment of inertia is 3.0kg•m^2
His final moment of inertia is 2.2kg•m^2.
Calculate the initial angular velocity:
L = 3.0π
Final angular velocity:
L = 2.2w
Set the initial and final angular momentum equal to each other and solve for the final angular velocity w:
3.0π = 2.2w
w = 1.4π rad/s
The rotational energy is given by:
KE = 0.5Iw^2
Initial rotational energy:
KE = 0.5(3.0)(π)^2 = 14.8J
Final rotational energy:
KE = 0.5(2.2)(1.4)^2 = 21.3J
There is an increase in rotational energy. Where did this energy come from? It came from changing the moment of inertia. The professor had to exert a radially inward force to pull in the dumbbells, doing work that increases his rotational energy.
