Answer:
a) W₁ = 8242.2 J, b) W₁ = 8242.2 J
, c) W₃ = 0
, d) W₄ = -189.51 J ,
f) v = 27.24 m / s
Explanation:
a) Work is defined by
W = F. d = F d sin θ
where angle is between force and displacement
n this case the suitcase is going up and the outside F is parallel to the plane, so the angle is zero and the cosine is 1
W = F d
Let's calculate
W = 169 3.8
W₁ = 8242.2 J
b) the gravitational force is vertical so it has an angle with respect to the horizontal parallel to the plane of
θ’= 90 - θ
θ'= 90-32 = 58º
W = m g d thing θ ’
W = 20 9.8 3.8 thing (180 + tea ’) =
W = 744.8 cos (180 + 32)
W₂ = -631.6 J
c) The normal work, as it has 90º with respect to the displacement, its work is zero
W₃ = 0
d) the work of the friction force
Let's write Newton's second law the Y axis
N- Wy = 0
Cos 32 = Wy / W
N = W cos 32
The expression for friction force is
fr = μ N
fr = μ mg cos 32
fr = 0.300 20 9.8 cos (32)
fr = 49.87 N
The work of the friction force
W = fr d cos 180
W₄ = -49.87 3.8
W₄ = -189.51 J
E) The total work
W = W₁ + W₂ + W₃ + W₄
W = 8242.2- 631.6 + 0 -189.51
W_total = 7421.09 J
F) Usmeosel theorem of work and energy
W = ΔK
W = ΔK = ½ m v² - 0
v =√ 2W / m
v = √ (2 7421.09 / 20)
v = 27.24 m / s
Answer:
a) 103.32 m
b) 9.18 s
Explanation:
a) Let's use the knowledge that at the top of its trajectory, the baseball will have a final velocity of 0 m/s.
The acceleration due to gravity is -9.8 m/s², assuming the upwards direction is positive and the downwards direction is negative.
The initial velocity of the baseball is 45 m/s.
We are trying to find the vertical displacement of the baseball, Δx, and we have the variables v, a, and v₀.
Find the constant acceleration equation that contains all four of these variables:
Substitute the known values into the equation.
- (0)² = (45)² + 2(-9.8)Δx
- 0 = 2025 - 19.6Δx
- -2025 = -19.6Δx
- Δx = 103.32
The maximum height of the ball before it falls back down is 103.32 m.
b) Now we want to solve for time t. Find a constant acceleration equation that contains three known variables.
Substitute known values into this equation.
- 0 = 45 + (-9.8)t
- -45 = -9.8t
- t = 4.59183673
Remember that this is only half of the baseball's flight since we are using the final velocity for when the ball is halfway through its trajectory.
To solve for the total time the baseball is in the air, double the time t we solved for.
The baseball is in the air for 9.18 s.
in ideal gas we have few things that we need to follow as following
1. Force of interaction between gas molecules are negligible.
2. There is no effect of gravity on them
3. All collisions are perfectly elastic collision.
4. there will be no energy loss
5. All newton's law are valid for them.
6. all molecules moves with same speed in random direction.
So here in order to follow all above conditions we have to maintain low pressure and high temperature in the gas due to which the density of gas becomes low.
So correct answer will be
<em>The gas density is low and the temperature is high.</em>
Answer:
A, True.
Explanation:
A heat engine converts heat into mechanical energy.
