Answer:
Explanation:
Photon is also a particle . Hence when two particles like electron and positron annihilate to get completely changed to photons , a minimum of two photons of equal and opposite momentum and energy are produced flying in opposite direction to conserve momentum and energy . Each photon will have same energy equal to 511 keV . It is so to conserve momentum and energy. Initially total momentum was zero so finally too total momentum should be zero.
Answer:
Angular acceleration of the disk will be 
Explanation:
We have given mass of the disk m = 5 kg
Diameter of the disk d = 30 cm = 0.3 m
So radius 
Moment of inertia of disk is given by 
Force is given by F=4 N
Torque is given as 
We also know that torque is given by 


Answer:
A₁/A₂ = 0.44
Explanation:
The emissive power of the bulb is given by the formula:
P = σεAT⁴
where,
P = Emissive Power
σ = Stefan-Boltzman constant
ε = Emissivity
A = Surface Area
T = Absolute Temperature of Surface
<u>FOR BULB 1:</u>
Since, emissivity and emissive power are constant.
Therefore,
P = σεA₁T₁⁴ ----------- equation 1
where,
A₁ = Surface Area of Bulb 1
T₁ = Temperature of Bulb 1 = 3000 k
<u>FOR BULB 2:</u>
Since, emissivity and emissive power are constant.
Therefore,
P = σεA₂T₂⁴ ----------- equation 2
where,
A₂ = Surface Area of Bulb 2
T₂ = Temperature of Bulb 1 = 2000 k
Dividing equation 1 by equation 2, we get:
P/P = σεA₁T₁⁴/σεA₂T₂⁴
1 = A₁(3000)²/A₂(2000)²
A₁/A₂ = (2000)²/(3000)²
<u>A₁/A₂ = 0.44</u>
Answer:
8.3
Explanation:
thats what i think sorry if its wrong im ok at doing this stuff
Answer:
67,032 J
Explanation:
According to the law of conservation of energy, the kinetic energy of the boulder just before hitting the Roadrunner (at ground level) will be equal to the gravitational potential energy of the boulder at the top of the cliff, therefore:

where
m is the mass of the boulder
g is the acceleration of gravity
h is the height of the cliff
Here we have
m = 76 kg
g = 9.8 m/s^2
h = 90 m
Substituting,
