Given:
P = 1000 W, power input
c = 4190 J/(kg-K), the specific heat of water
m = 1 kg, mass of water
ΔT = 10 °C = 10 K, temperature rise.
Let t = time required to raise the temperature f the water.
Then
P*t = m*c*ΔT
(1000 J/s)*(t s) = (1 kg)*(4190 J/(kg-K)*(10 K)
1000t = 41900
t = 41.9 s
Answer: 41.9 s or 42 s (approximately)
<u>Answer:</u> The Fermi velocity of lead is 64.4 km/s.
<u>Explanation:</u>
To calculate the Fermi velocity, we use the equation:

where,
h = Planck's constant = 
= mass of electron = 
N = Number of atoms present in per volume of atom multiplied by number of electrons present in given atom = 
= Avogadro's number =
(When the mass is in kilograms)
V = Volume = 
M = molecular weight of lead = 207.2 g/mol
Putting values in above equation, we get:

(Conversion factor: 1 km = 1000 m)
Hence, the Fermi velocity of lead is 64.4 km/s
<span>Work done on charge is W = Eqd = σ/(2ε₀) x q x d = {(8.00 x 10⁻¹²)/(2 x 8.854187 x 10⁻¹²)} x 3.00 x 10⁻⁶ x (0.650 - 0.250) = 5.42116402J. KE of sphere = 0.5mv² = 0.5 x 5.00 x 10⁻⁷v² = work done by E-field on charge during its fall = 5.42116402→ v = 4657 m/s.</span>
Answer:
1) It expresses the rate (top speed) at which it can move with time.
2) P = 20 W
3) h = 18 km
Explanation:
1) Power is the rate of transfer of energy.
⇒ Power = 
i.e P = 
Thus a car's engine power is 44000W implies that the engine of the car can propel the car at this rate. This expresses the rate (top speed) at which it can move with time.
2) m = 400g = 0.4 kg
t = 20 s
h = 100m
g = 10 m/
P = 
= 
= 
P = 20 W
3) u = 600 m/s
g = 10 m/
From the third equation of free fall,
=
- 2gh
V is the final velocity, U is the initial velocity, h is the height.
0 =
- 2 x 10 x h
0 = 360000 - 20h
20h = 360000
h = 
= 18000
h = 18 km
The maximum height of the bullet would be 18 km.
In a series circuit, all devices are constrained to a single flow of current. There can only be a single value for the current for all devices, otherwise this would violate the conservation of charge. Therefore the current must be the same across each resistor.
<h3>The answer is D.</h3>