Answer:
ΔS= -1 J/K
Explanation:
Given data
Heat Q= -470J
Temperature T=470 K
To find
Entropy change ΔS
Solution
We know that the entropy change of system is ΔS is given by
ΔS=Q/T
We have take heat value Q as negative because the heat is removed from heat reservoir
So
ΔS=(-470J/470K)
ΔS= -1 J/K
Answer:
Explanation:
First, we can find the mass of the object in air
Since W = mg
m = W/g = (8.9)/(9.8) = 0.908 kg
Then, by Archimedes principle, we can find its volume. The volume is found by the weight of the water displaced by the formula
W = Vρg
The Weight is the difference in scale readings. The density of water is 1000 kg/m3
(8.9- 7.8) = V(1000)(9.8)
Thus V = 1 X 10-4 m3
Then, since density is mass / volume
ρ = 0.908/1 X 10-4
ρ = 8254 kg/m3 which is 8 X 103 kg/m3
The density of gold is 19.3 X 103 kg/m3
Since those densities are not the same, the crown is either hollow or not pure gold
Answer:
Periods are 60 seconds, 60 minutes and 12 hours frequency are their reciprocal.
Explanation:
For second hand, period = 1 min = 3660 s; frequency = 0.0166
For minute hand, period = 1 hr = 3600 s; frequency = 2.77}
For hour hand, period = 12 hrs = 4300 s; frequency = 2.3}
Mass of yellow train, my = 100 kg
Initial Velocity of yellow train, = 8 m/s
mass of orange train = 200 kg
Initial Velocity of orange train = -1 m/s (since it moves opposite direction to the yellow train, we will put negative to show the opposite direction)
To calculate the initial momentum of both trains, we will use the principle of conservation of momentum which
The sum of initial momentum = the sum of final momentum
Since the question only wants the sum of initial momentum,
(100)(8) + (200)(-1) = 600 m/s
Answer: Option A : Technician A
Explanation:
The statement/observation, "that the starter motor used to crank diesel engines can draw up to 400 amps of current" made by Technician A is correct.
A diesel engine uses up to 400+ Amperes of electricity to start up a diesel engine in the ignition chamber of motor engine.