The weight of an object is taken to be the force on the object due to gravity. The weight ( W ) is the product of the mass ( m ) of the object and the magnitude of the gravitational acceleration ( g ).
On Earth: g = 9.81 m/s²
m = 20 kg
W = m · g = 20 kg · 9.81 m/s² = 196.2 N
Answer:
1.2 m/s
0.31 m
0.15 m
Explanation:
Time period is

Frequency is

Velocity is given by

The waves are traveling at 1.2 m/s
Amplitude is given by

Amplitude is 0.31 m
If d = 0.3 m

The amplitude would be 0.15 m. The speed would remain the same.
Answer:
ΔU = - 310.6 J (negative sign indicates decrease in internal energy)
W = 810.6 J
Explanation:
a.
Using first law of thermodynamics:
Q = ΔU + W
where,
Q = Heat Absorbed = 500 J
ΔU = Change in Internal Energy of Gas = ?
W = Work Done = PΔV =
P = Pressure = 2 atm = 202650 Pa
ΔV = Change in Volume = 10 L - 6 L = 4 L = 0.004 m³
Therefore,
Q = ΔU + PΔV
500 J = ΔU + (202650 Pa)(0.004 m³)
ΔU = 500 J - 810.6 J
<u>ΔU = - 310.6 J (negative sign indicates decrease in internal energy)</u>
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b.
The work done can be simply calculated as:
W = PΔV
W = (202650 Pa)(0.004 m³)
<u>W = 810.6 J</u>
John used smothering as the method to control the harmful invasive plants in his orchard. Smothering is an example of a manual method of control and it works best in a small population of invasive species. Smothering involves covering the invasive species with a barrier that is highly impenetrable for one growing season in order to prevent these species from thriving in the environment.
Answer:
1470 W
Explanation:
Power: This can be defined as the rate at which work is done or energy is used up. The S.I unit of power is Watt (W).
The expression for power is given as,
P = Energy/time
P = mgh/t ...................... Equation 1
Where P = power, m = mass, h = height, t = time, g = acceleration due to gravity.
Given: m = 75 kg, g =9.8 m/s², h = 1 m, t = 1 s.
Substitute into equation 1
P = (75×1×9.8)/1
P = 735 W.
From the above,
1 hp = 735 W
2 hp = (2×735) W
2 hp = 1470 W.
Hence 2 hp = 1470 W