1.
Answer:
Metallic plates emit electrons only when light of a certain minimum frequency shines on them.
Explanation:
As we know by Einstein's equation of energy
here we know that
= work function of metal
KE = kinetic energy of ejected electrons
E = energy of incident light
So here electrons will eject only when light of sufficient minimum energy will incident on the metal plate.
2.
Answer:
showed that individual photons have wave characteristics
Explanation:
Taylor did experiment with the source of light with very small intensity of light and then got the result of interference of light.
So here his experiment concluded that all light will show interference only due to one photon also.
So his experiment shows that one photon will give wave characteristics
#1
so mass number = 238
mass number = protons + neutrons
given that
neutrons = 146
238 = protons + 146
protons = 92
#2
so mass number = 241
mass number = protons + neutrons
given that
Protons = 94
241 = 94 + neutrons
neutrons = 147
#3
A = mass number
Protons = 90
Neutrons = 137
A = protons + Neutrons
A = 90 + 137 = 227
Answer:
A. Increase in temperature is 0.0176 degree Celsius. b. the remaining energy will be lost.
Explanation:
The mass of copper block = 7kg
Initial speed = 4.0 m/s
Specific heat of copper = 0.385 j/g degree Celcius.
a. The increase in temperature is calculated below:
85% of energy is converted into internal energy.
b. The remaining 15 per cent of kinetic energy will be lost and it will be changed into other forms.
Answer:
h = v₀² / 2g , h = k/4g x²
Explanation:
In this exercise we can use the law of conservation of energy at two points, the lowest, before the shot and the highest point that the mouse reaches
Starting point. Lower compressed spring
Em₀ = K = ½ m v²
Final point. Highest on the path
= U = mg h
As or no friction the energy is conserved
Em₀ = Em_{f}
½ m v₀²² = m g h
h = v₀² / 2g
We can also use as initial energy the energy stored in the spring that will later be transferred to the mouse
½ k x² = 2 g h
h = k/4g x²
Answer:
The heater power required is 2400 W. The power in the heater can be calculated as the product of the voltage line and the steady current:
Explanation: