Answer:
Explanation:
Since energy is conserved:
2
mu
2
=
2
mv
2
+mgh
⇒u
2
=v
2
+2gh
⇒(3)
2
=v
2
+2(9.8)(0.5−0.5cos60)
⇒v=2m/s
Answer:
Work: 4.0 kJ, heat: 4.25 kJ
Explanation:
For a gas transformation at constant pressure, the work done by the gas is given by

where in this case we have:
is the pressure
is the initial volume
is the final volume
Substituting,

The 1st law of thermodynamics also states that

where
is the change in internal energy of the gas
Q is the heat absorbed by the gas
Here we know that

Therefore we can re-arrange the equation to find the heat absorbed by the gas:

Answer:
Option C
100 J
Explanation:
Kinetic energy, KE is given by
where m is the mass and v is the velocity
Substituting 50 Kg for mass, m and 2 m/s for velocity v then we obtain

Therefore, the child's kinetic energy is equivalent to 100 J
Answer:
Fnet = F√2
Fnet = kq²/r² √2
Explanation:
A exerts a force F on B, and C exerts an equal force F on B perpendicular to that. The net force can be found with Pythagorean theorem:
Fnet = √(F² + F²)
Fnet = F√2
The force between two charges particles is:
F = k q₁ q₂ / r²
where
k is Coulomb's constant, q₁ and q₂ are the charges, and r is the distance between the charges.
If we say the charge of each particle is q, then:
F = kq²/r²
Substituting:
Fnet = kq²/r² √2
Answer:
The value is
Explanation:
From the question we are told that
The wavelength is 
The velocity is 
The mass of electron is 
Generally the energy of the incident light is mathematically represented as

Here c is the speed of light with value
h is the Planck constant with value 
So

=> 
Generally the kinetic energy is mathematically represented as

=> 
=> 
Generally the ionization energy is mathematically represented as

=>