B - speed and direction are combined in another quantity, called velocity. It can be thought of as its speed in a particular direction. Speed is the corresponding scalar quantity, because it does not have a direction.
v₀ = initial speed of the object = 8 meter/second
v = final speed of the object = 16 meter/second
t = time taken to increase the speed = 10 seconds
d = distance traveled by the object in the given time duration = ?
using the kinematics equation
d = (v + v₀) t/2
inserting the above values in the above equation
d = (16 + 8) (10)/2
d = 120 meter
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>
Velocity is distance/time
so 150/7200=.0208km/s
unless you have to convert it to miles or something else. but use the formula!
