Answer:
1. A1, B2, C3
2. 47.1°
Explanation:
Sum of forces in the x direction:
∑Fₓ = ma
f − Fᵥᵥ = 0
f = Fᵥᵥ
Sum of forces in the y direction:
∑Fᵧ = ma
N − W = 0
N = W
Sum of moments about the base of the ladder:
∑τ = Iα
Fᵥᵥ h − W (b/2) = 0
Fᵥᵥ h = ½ W b
Fᵥᵥ (l sin θ) = ½ W (l cos θ)
l Fᵥᵥ sin θ = ½ l W cos θ
The correct set of equations is A1, B2, C3.
At the smallest angle θ, f = Nμ. Substituting into the first equation, we get:
Nμ = Fᵥᵥ
Substituting the second equation into this equation, we get:
Wμ = Fᵥᵥ
Substituting this into the third equation, we get:
l (Wμ) sin θ = ½ l W cos θ
μ sin θ = ½ cos θ
tan θ = 1 / (2μ)
θ = atan(1 / (2μ))
θ = atan(1 / (2 × 0.464))
θ ≈ 47.1°
Effect of temperature.
"If the temperature of the substance is increased then the rate of chemical reaction is also increased because the kinetic energy is greater."
Effect of surface area.
"If the surface area is increased then the rate of reaction is increased because there will be more active sites for the reaction to occur.
<u>Harmful</u><u />
-causes heat; if it's not used correctly, it can cause injury
-when falling, the friction between your knee/leg and the ground can cause scrapes
<u>
</u><u>Helpful</u><u />
-helps stop the bike, the brakes rub against the tire which slows it down to a stop
-it can also help move the bike; the chains rub against tires which accelerate the bike
Answer:
Average velocity (v) of an object is equal to its final velocity (v) plus initial velocity (u), divided by two.
v¯¯¯=(v+u)2
Where:
v¯¯¯ = average velocity
v = final velocity
u = initial velocity
The average velocity calculator solves for the average velocity using the same method as finding the average of any two numbers. The sum of the initial and final velocity is divided by 2 to find the average. The average velocity calculator uses the formula that shows the average velocity (v) equals the sum of the final velocity (v) and the initial velocity (u), divided by 2.
Explanation:
Answer:
Work and Kinetic Energy
A B
3. A 0.180 kg balls falls 2.5 m. How much work does the force of gravity do on the ball? 4.41 J
4. A forklift raises a box 1.2 m doing 7.0 kJ of work on it. What is the mass of the box? 595.24 kg
5. How much work does the force of gravity do when a 25 N object falls a distance of 3.5 m? 87.5 J
Explanation:
