Answer:
7800 J
Explanation:
Heat needed = mass of copper x specific heat of copper x change in temperature
Change in temperature = 30ºC - 20ºC = 10ºC
Specific heat of copper = 390 J/kgºC
Mass of copper = 2 Kg
Substituting the given values in above equation, we get –
Heat needed = 2 Kg x 390 J/kgºC x 10ºC
= 7800 J
The faster the job is done, the greater the power
Answer:
Part a)
T = 0.52 s
Part b)

Part c)

Explanation:
As we know that the particle move from its maximum displacement to its mean position in t = 0.13 s
so total time period of the particle is given as

now we have
Part a)
T = time to complete one oscillation
so here it will move to and fro for one complete oscillation
so T = 0.52 s
Part b)
As we know that frequency and time period related to each other as



Part c)
As we know that
wavelength = 1.9 m
frequency = 1.92 Hz
so wave speed is given as



<span> Let’s determine the initial momentum of each car.
#1 = 998 * 20 = 19,960
#2 = 1200 * 17 = 20,400
This is this is total momentum in the x direction before the collision. B is the correct answer. Since momentum is conserved in both directions, this will be total momentum is the x direction after the collision. To prove that this is true, let’s determine the magnitude and direction of the total momentum after the collision.
Since the y axis and the x axis are perpendicular to each other, use the following equation to determine the magnitude of their final momentum.
Final = √(x^2 + y^2) = √(20,400^2 + 19,960^2) = √814,561,600
This is approximately 28,541. To determine the x component, we need to determine the angle of the final momentum. Use the following equation.
Tan θ = y/x = 19,960/20,400 = 499/510
θ = tan^-1 (499/510)
The angle is approximately 43.85˚ counter clockwise from the negative x axis. To determine the x component, multiply the final momentum by the cosine of the angle.
x = √814,561,600 * cos (tan^-1 (499/510) = 20,400</span>
Answer:
205 V
V
= 2.05 V
Explanation:
L = Inductance in Henries, (H) = 0.500 H
resistor is of 93 Ω so R = 93 Ω
The voltage across the inductor is

w = 500 rad/s
IwL = 11.0 V
Current:
I = 11.0 V / wL
= 11.0 V / 500 rad/s (0.500 H)
= 11.0 / 250
I = 0.044 A
Now
V
= IR
= (0.044 A) (93 Ω)
V
= 4.092 V
Deriving formula for voltage across the resistor
The derivative of sin is cos
V
= V
cos (wt)
Putting V
= 4.092 V and w = 500 rad/s
V
= V
cos (wt)
= (4.092 V) (cos(500 rad/s )t)
So the voltage across the resistor at 2.09 x 10-3 s is which means
t = 2.09 x 10⁻³
V
= (4.092 V) (cos (500 rads/s)(2.09 x 10⁻³s))
= (4.092 V) (cos (500 rads/s)(0.00209))
= (4.092 V) (cos(1.045))
= (4.092 V)(0.501902)
= 2.053783
V
= 2.05 V