Answer:
Vy = V0 sin 38 where Vy is the initial vertical velocity
The ball will accelerate downwards (until it lands)
Note the signs involved if Vy is positive then g must be negative
The acceleration is constant until the ball lands
t (upwards) = (0 - Vy) / -g = Vy / g final velocity = 0
t(downwards = (-Vy - 0) / -g = Vy / g final velocity = -Vy
time upwards = time downwards (conservation laws)
First let us calculate for the angle of inclination using
the sin function,
sin θ = 1 m / 4 m
θ = 14.48°
Then we calculate the work done by the movers using the
formula:
W = Fnet * d
So we must calculate for the value of Fnet first. Fnet is
force due to weight minus the frictional force.
Fnet = m g sinθ – μ m g cosθ
Fnet = 1,500 sin14.48 – 0.2 * 1,500 * cos14.48
Fnet = 84.526 N
So the work exerted is equal to:
W = 84.526 N * 4 m
<span>W = 338.10 J</span>
Answer:
0.1111 W/m²
Explanation:
If all other parameters are constant, sound intensity is inversely proportional to the square of the distance of the sound. That is,
I ∝ (1/r²)
I = k/r²
Since k can be the constant of proportionality. k = Ir²
We can write this relation as
I₁ × r₁² = I₂ × r₂²
I₁ = 0.25 W/m²
r₁ = 16 m
I₂ = ?
r₂ = 24 m
0.25 × 16² = I₂ × 24²
I₂ = (0.25 × 16²)/24²
I₂ = 0.1111 W/m²
Answer:
Both have the same amount. C.
Explanation: