Answer:
Explanation:
Constant pressure molar heat capacity Cp = 29.125 J /K.mol
If Cv be constant volume molar heat capacity
Cp - Cv = R
Cv = Cp - R
= 29.125 - 8.314 J
= 20.811 J
change in internal energy = n x Cv x Δ T
n is number of moles , Cv is molar heat capacity at constant volume , Δ T is change in temperature
Putting the values
= 20 x 20.811 x 15
= 6243.3 J.
Answer: there are 15 coins of $2 and 18 coins of $5
Explanation:
I will answer in English.
X is the number of $5 coins.
Y is the number of $2 coins.
We have the system of equations:
Y + X = 33
Y*2 + X*5 = 120
first, we must isolate one of the variables in one of the equations and then replace it in the other equation, let's isolate Y in the first equation:
Y = 33 - X.
Then we can replace it in the other equation:
(33 - X)*2 + X*5 = 120
66 - X*2 + X*5 = 120
X*3 = 54
X = 54/3 = 18
and using the equation for Y.
Y = 33 - X = 33 - 18 = 15
So there are 15 coins of $2 and 18 coins of $5
Answer:
x = v₀ cos θ t
, y = y₀ + v₀ sin θ t - ½ g t2
Explanation:
This is a projectile launch exercise, in this case we will write the equations for the x and y axes
Let's use trigonometry to find the components of the initial velocity
sin θ =
/ v₀
cos θ = v₀ₓ / v₀
v_{y} = v_{oy} sin θ
v₀ₓ = vo cos θ
now let's write the equations of motion
X axis
x = v₀ₓ t
x = v₀ cos θ t
vₓ = v₀ cos θ
Y axis
y = y₀ +
t - ½ g t2
y = y₀ + v₀ sin θ t - ½ g t2
v_{y} = v₀ - g t
v_{y} = v₀ sin θ - gt
= v_{oy}^2 sin² θ - 2 g y
As we can see the fundamental change is that between the horizontal launch and the inclined launch, the velocity has components
Answer:
The car strikes the tree with a final speed of 4.165 m/s
The acceleration need to be of -5.19 m/seg2 to avoid collision by 0.5m
Explanation:
First we need to calculate the initial speed 
Once we have the initial speed, we can isolate the final speed from following equation:
Then we can calculate the aceleration where the car stops 0.5 m before striking the tree.
To do that, we replace 62 m in the first formula, as follows:

Answer:
23.1 N/C
Explanation:
OP = 3 m , OQ = 4 m

q = - 8 nC, Q = 75 nC
Electric field at P due to the charge Q is

Electric field at P due to the charge q is

According to the diagram, tanθ = 3/4
Resolve the components of E1 along x axis and along y axis.
So, Electric field along X axis, Ex = - E1 Cos θ
Ex = - 27 x 4 / 5 = - 21.6 N/C
Electric field along y axis, Ey = E1 Sinθ - E2
Ey = 27 x 3 /5 - 8 = 8.2 N/C
The resultant electric field at P is given by
