Inverse square law:
where
is the intensity at distance 1
is the intensity at distance 2
is distance 1
is distance 2
The inverse squared law state that intensity decreases in inverse proportion to the distance squared. So if light obeyed that rule, it will decreases its intensity as the square of the distance increases.
We can conclude that the correct answer is:
true.
Answer:
E = 75 J
Explanation:
First, we will calculate the total power consumed by the five lamps:
Now, the energy supply can be calculated as follows:
where,
E = Energy = ?
t = time = 5 s
Therefore,
E = (15 W)(5 s)
<u>E = 75 J</u>
Answer:
c = 4,444.44
Explanation:
You have the following expression for the acceleration of the projectile:
(1)
s: distance to the ground of the projectile
To find the value of the constant c you use the following formula:
(2)
vo: initial velocity = 0 m/s
v: final speed = 200 m/s
Δs: distance traveled by the projectile = 3m - 1.5m = 1.5m
You replace the expression (1) into the expression (2):
You do the constant c in the last equation, then you replace the values of v, s and Δs:
Answer:
Exercise 1;
The centripetal acceleration is approximately 94.52 m/s²
Explanation:
1) The given parameters are;
The diameter of the circle = 8 cm = 0.08 m
The radius of the circle = Diameter/2 = 0.08/2 = 0.04 m
The speed of motion = 7 km/h = 1.944444 m/s
The centripetal acceleration = v²/r = 1.944444²/0.04 ≈ 94.52 m/s²
The centripetal acceleration ≈ 94.52 m/s²
Answer:
velocity at the top: 0 m/s
acceleration at the top: -9.8 m/s²
Explanation:
Assuming up is positive and down is negative;
The velocity of the ball at the top of its path will be 0 m/s and the acceleration will be negative.
The velocity is 0 m/s because the ball does not move at the top of its path, and it switches from a positive velocity to a negative velocity. It must go through 0 in order to go from positive to negative.
The acceleration, however, is always negative no matter where the ball is in its motion. This negative acceleration causes the ball to slow down as it reaches the top, and speed up as it reaches the bottom.
<u>Think about it:</u> If there wasn't a negative acceleration, and it was instead 0, the ball would never come back down and instead keep going in a straight line.
