Answer:
1.23×10⁶ J
Explanation:
From the question given above, the following data were obtained:
Velocity (v) = 65 m/s
Mass (m) = 580 Kg
Kinetic energy (KE) =?
The kinetic energy can be obtained by using the following formula :
KE = ½mv²
Where:
KE => is the kinetic energy.
m => is the mass
v => is the velocity
With the above formula, we can obtain the kinetic energy as follow:
Velocity (v) = 65 m/s
Mass (m) = 580 Kg
Kinetic energy (KE) =?
KE = ½mv²
KE = ½ × 580 × 65²
KE= 290 × 4225
KE = 1.23×10⁶ J
Thus, the kinetic energy is 1.23×10⁶ J
Triple beam balance/scale to find mass, and graduated cylinder to find volume
Answer:
(a) 
(b) 
Explanation:
Given data
The source is 1.00 μW
The point is 3m away from the point source
For Part (a)
The intensity at a certain distance from a point source that emits sound wave is given as:

For Part (b)
The Sound level is given by
β=(10dB)×log(I/I₀)
Where
I₀=1×10⁻¹²W/m²
Substitute the given values to find Sound level
So

In the above problem, we need to find mass of the second child, so that the Center of Mass remains at the origin( pivot).
CM= m1r1+m2r2/m1+m2
0= 20*-2+16*r2/20+16
r2= 40/16
r2= +2.5 m
The answer is <span>A. Speed=100 million m/s and frequency = 50 million Hz.</span>
Let's calculate for each choice the wavelength using the equation:
v = f × λ ⇒ λ = v ÷ f<span>
where:
v - the speed,
f - the frequency,
</span>λ - the wavelength.
A:
v = 100 000 000 m/s
f = 50 000 000 Hz = 50 000 000 1/s (Since f = 1/T, so units are Hz = 1/s)
⇒ λ = 100 000 000 ÷ 50 000 000 = 2 m
B:
v = 150 000 000 m/s
f = 1 500 Hz = 1 500 1/s
⇒ λ = 150 000 000 m/s ÷ 1 500 = 100 000 m
B:
v = 300 000 000 m/s
f = 100 Hz = 100 1/s
⇒ λ = 300 000 000 m/s ÷ 100 = 3 000 000 m
According to these calculations, the shortest wavelength is needed for choice A.