Answer:
Part A: 16.1 V
Part B: 20.5 V
Part C: 21.5%
Explanation:
The voltmeter is in parallel with the 4.5-kΩ resistor and the combination is in series with the 6.5-kΩ resistor. The equivalent resistance of the parallel combination is given as


Part A
The voltmeter reading is the potential difference across the parallel combination. This is found by using the voltage-divider rule.

Part B
Without the voltmeter, the potential difference across the 4.5-kΩ resistor is found using the same rule as above:

Part C
The error in % is given by

(a). If the temperature of a substance is increased the density of it will also increased. The temperature is directly proportional to the density because the molecular activity of the substance will be affected by the temperature
(b).The mass of the substance doesn't at all. Because the amount of matter inside the substance cannot be affected by the temperature except that its water
Answer:
Explanation:
From the given information:
The initial PE
= m×g×h
= 5 kg × 9.81 m/s² × 10 m
= 490.5 J
The change in Potential energy P.E of the box is:
ΔP.E = 
ΔP.E = 0 -
ΔP.E = 
If we take a look at conservation of total energy for determining the change in the internal energy of the box;


this can be re-written as:

Here, K.E = 0
Also, 70% goes into raising the internal energy for the box;
Thus,


ΔU = 343.35 J
Thus, the magnitude of the increase is = 343.35 J