Answer:
K.E = 30,000 J
Explanation:
Given,
The potential energy of the roller coaster car, P.E = 40000 J
The kinetic energy at height h/4, K.E = ?
According to the law of conservation of energy, the total energy of the system is conserved.
At height 'h', the total energy is,
P.E = mgh
K.E = 0
At height 'h/4', the total energy is
P.E + K.E = mgh
P.E = mgh/4
K.E = 1/2 mv²
Therefore,
mgh/4 + 1/2 mv² = mgh
gh/4 + v²/2 = gh
Hence,
v² = 3gh/2
Substituting in the K.E equation
K.E = 1/2 mv²
= 1/2 m (3gh/2)
= 3/4 mgh
= 3/4 x 40000
= 30000 J
Hence, the K.E of the roller coaster car is, K.E = 30000 J
Metals contain the most and semiconductors contain the least amount. Hope this helps.
Answer:
C.
If he is pulled into a current, he should swim toward the shore at a 45-degree angle.
Explanation:
Answer:
show the list of things or a picture so I can answer it
Answer:
The bulb with higher temperature(4000 K) will be brighter
Explanation:
From the question we are told that
The color temperature for first bulb is 
The color temperature for second bulb is 
Generally the emission power of black body radiation is mathematically represented as

Where
is the Stefan-Boltzmann constant with a value 
Now for 


At 


Looking at the result we got we see that the emission power for the higher temperature bulb is higher, this means that its power to emit in the visible spectrum range would be higher
So the bulb with higher temperature will be brighter