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>
<u></u>
b.
The work done can be simply calculated as:
W = PΔV
W = (202650 Pa)(0.004 m³)
<u>W = 810.6 J</u>
Answer:
207.4 N
Explanation:
The torque
on a body is
where r is the radius vector from the point of rotation to the point at which force F is applied.
The product of r and F is equal to the product of magnitude of r and F multiplied by the sine of angle between both vectors.
Therefore, torque is also given by
Where
is the angle between r and F.
Use the expression of torque.
Substitute L for r in the equation
Where L is the length of the wrench.
Making F the subject
Force required to pull the wrench is given as,
Substitute
for
, 25 cm for L, and 115o for
Answer:
7.36 × 10^22 kg
Explanation:
Mass of the man = 90kg
Weight on the moon = 146N
radius of the moon =1.74×10^6
Weight =mg
g= weight/mass
g= 146/90 = 1.62m/s^2
From the law of gravitational force
g = GM/r^2
Where G = 6.67 ×10^-11
M = gr^2/G
M= 1.62 × (1.74×10^6)^2/6.67×10^-11
= 4.904×10^12/6.67×10^-11
=0.735×10^23
M= 7.35×10^22kg. (approximately) with option c
<span>Weight of the skydiver m = 500 N
Terminal velocity V = 90 km/h
Here the weight of the person acts as the force, so based on the Newton's third law the applied is the force what we but in the opposite direction making the resistance. So the air resistance exerted on Suzie will be her weight that is 500N</span>