Heat required to change the phase of ice is given by
Q = m* L
here 
m = mass of ice
L = latent heat of fusion
now we have
m = 45 kg
L = 334 KJ/kg
now by using above formula


In KJ we can convert this as

so the correct answer is D option
 
        
                    
             
        
        
        
Answer:
The answers to the questions have been solved in the attachment.
Explanation:
The answers to part a to e are all contained in the attachment. For answer part b, temperature and frequency were assumed to be fixed or constant. V² is directly proportional to T telling us that variation in T gives us a square in the frequency variation. This tells us why it is difficult when both frequencies are on this side of the black body.
 
        
             
        
        
        
Answer:
The magnitude of the magnetic field is  .
.
Explanation:
Given that,
Charge, 
Speed of the charged particle, 
The angle between the velocity of the charge and the field is 56°. 
The magnitude of force, 
We need to find the magnitude of the magnetic field. When a charged particle moves in the magnetic field, the magnetic force is experienced by it. The force is given by :

B is the magnetic field.

So, the magnitude of the magnetic field is  . Hence, this is the required solution.
. Hence, this is the required solution. 
 
        
             
        
        
        
Mechanical energy E = mgh + 1/2mv²
When he starts, let h = 0 ⇒ E₁ = 1/2mv₁²
When he reaches height h ⇒ E₂ = mgh + 1/2mv₂²
Without friction, energy is conserved at all times.
E₁ = E₂
     ↓
1/2mv₁² = mgh + 1/2mv₂²
     ↓
1/2v₁² = gh + 1/2v₂²
     ↓
gh = 1/2(v₁² - v₂²)
    ↓
h = (v₁² - v₂²) / (2g)
        
                    
             
        
        
        
Answer:
Cosmic ray's frame of reference: 99,875 years
Stationary frame of reference: 501,891 years
Explanation:
First of all, we convert the distance from parsec into metres:

The speed of the cosmic ray is

where
 is the speed of light. Substituting,
 is the speed of light. Substituting,

And so, the time taken to complete the journey in the cosmic's ray frame of reference (called proper time) is:

Converting into years,

Instead, the time elapsed in the stationary frame of reference is given by Lorentz transformation:

And substituting v = 0.98c, we find:
