1. U = Q + W
U = -500 + 1000
U = 500 J
2. The first law of thermodynamic is about the law of conservation of energy where energy in should be equal to energy out.
3. It is the windmill that does not transform energy from heat to mechanical instead it is the transforms the opposite.
4. In a heat engine, work is used to transfer thermal energy from a hot reservoir to a cold one.
5. 5.00 × 10^4 J - 2.00 × 10^4 J = 3.00 × 10^4 J
6. To increase the work done, we raise the temperature of the cold reservoir.
To develop this problem it is necessary to apply the concepts related to the kinematic equations of motion. And from the speed found the relationships between wavelength, frequency and last of the period (which is inversely proportional to the frequency)
PART A) We know that the velocity of a body or a wave is equivalent to the distance traveled over a time interval. So,
Where
x = Distance
t = time
PART B) The frequency would then be defined as
Where
PART C) Finally the period is defined as
Answer:
a)W= 1 J
b)W= 1 J
c)W= 0 J
Explanation:
Given that
m = 5 kg
Coefficient of kinetic friction,K=0.5
d= 10 cm
We know that if velocity is constant it means that the acceleration of the system is zero.Or we can say that all forces are balance in the system.
We know that work is the dot product of force and displacement
W= F.d
The friction force on the box
Fr= K m g
Fr= 0.5 x 5 x 10 = 25 N ( take g =10 m/s²)
Fr=25 N
a)
Acceleration a= 0
So horizontal force F = Fr
W = Fr.d
W=10 x 0.1 J
W= 1 J
b)
The work done by friction force
W= 1 J
c)
The net force on the system is zero because acceleration is zero.
F= 0
So
W= 0 J
Answer:
Their kinetic energies would be the same
Explanation:
This is because, since the force, F acting on them moves the same distance, d, the work done by the force is W = Fd.
Now, from work-kinetic energy principles,
W = ΔK where ΔK = change in kinetic energy of the carts.
Since the work-done is the same for both carts, their change in kinetic energies would also be the same.
Since they start from rest, ΔK = K' - K = K' - 0 = K'
So, the kinetic energies of the carts would be the same
Answer:
v₀ = 15 m/s
Explanation:
given,
initial velocity = v₀
down acceleration of rock = 10 m/s²
rock distance
S₄ = 7 x S₁
From kinematic equations
S = v₀ t+0.5 at²
at t = 1 s
S₁ = v₀ (1)+0.5 x 10 x 1²
S₁ = v₀+ 5......(1)
at t = 4 s
S₄ = v₀ (4)+0.5 x 10 x 4²
S₄ = 4 v₀+80.....(2)
from equation (1) and (2)
7( v₀ + 5 ) = 4 v₀ +80
3 v₀ = 80 - 35
3 v₀ = 45
v₀ = 15 m/s
