A. freezing, when water turns to ice the water is turning from a liquid to a solid.
Answer: V = 15 m/s
Explanation:
As stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. The observed frequency the car will be experiencing will be addition of the two frequency. That is,
F = 2.1 × 10^10 + 1030 = 2.100000103×10^10Hz
Using doppler effect formula
F = C/ ( C - V) × f
Where
F = observed frequency
f = source frequency
C = speed of light = 3×10^8
V = speed of the car
Substitute all the parameters into the formula
2.100000103×10^10 = 3×10^8/(3×10^8 -V) × 2.1×10^10
2.100000103×10^10/2.1×10^10 = 3×108/(3×10^8 - V)
1.000000049 = 3×10^8/(3×10^8 - V)
Cross multiply
300000014.7 - 1.000000049V = 3×10^8
Collect the like terms
1.000000049V = 14.71429
Make V the subject of formula
V = 14.71429/1.000000049
V = 14.7 m/s
The speed of the car is 15 m/s approximately
Answer:
W = 0.49 N
τ = 0.4851 Nm
Force
Explanation:
The weight force can be found as:
W = mg
W = (0.05 kg)(9.8 m/s²)
<u>W = 0.49 N</u>
The torque about the pivot can be found as:
τ = W*d
where,
τ = torque
d = distance between weight and pivot = 99 cm = 0.99 m
Therefore,
τ = (0.49 N)(0.99 m)
<u>τ = 0.4851 Nm</u>
The pivot exerts a <u>FORCE </u>on the meter stick because the pivot applies force normally over the stick and has a zero distance from stick.
