Answer:
the signs of heat and work are; -Q and -W
Explanation:
The first law of thermodynamics is given by; ΔU = Q − W
where;
ΔU is the change in internal energy of a system,
Q is the net heat transfer (the sum of all heat transfer into and out of the system)
W is the net work done (the sum of all work done on or by the system).
Now, The system in this case is the tire and since the air gets warmer, heat must have left the system. Therefore Q is negative (-Q).
Since work is done by the system, W remains negative.
Thus, the signs of heat and work are; -Q and - W
Answer:
The points 2 and 4 should be connected.
Explanation:
To complete the circuit, we need to connect the two points which when connected, encompass the battery and the bulb in the circuit. The points 2 and 4 do the job, since they connect the terminal of the battery and the terminal of the bulb, and thus complete the circuit.
Therefore, the choice C is correct.
Given:
Time: 3.5 hrs
Velocity: 120 miles/hr
Now Distance= Speed × Time
Now Velocity and speed have the same magnitude. Velocity being a vector quantity has a definite direction. Whereas speed is a scalar quantity,it indicates only the magnitude an doesn't define any direction.
Hence Distance = Velocity x time
Distance = 3.5 × 120 = 420 miles
C. The number of F atoms in the reactants equals the number of F atoms in the products.
Answer:
between the plates.
Explanation:
The equation for change of voltage between two points separated a distance d inside parallel conducting plates (<em>which have between them constant electric field</em>) is:
So to calculate our electric field strength we use the fact that the potential 8.8 cm from the zero volt plate is 475 V:
And we use the fact that the plates are 9.2cm apart to calculate the voltage between them:
