Answer:
S=48.29 m
Explanation:
Given that the height of the hill h = 2.9 m
Coefficient of kinetic friction between his sled and the snow μ = 0.08
Let u be the speed of the skier at the bottom of the hill.
By applying conservation of energy at the top and bottom of the inclined plane we get.
Potential Energy=kinetic Energy
mgh = (1/2) mu²
u² = 2gh
u²=2(9.81)(2.9)
=56.89
u=7.54 m/s
a = - f / m
a = - μ*m*g / m
a = - μg
From equation of motion
v²- u² = 2 -μ g S
v=0 m/s
-(7.54)²=-2(0.06)(9.81)S
S=48.29 m
Answer:
11.7 m/s
Explanation:
To find its speed, we first find the acceleration of the center of mass of a rolling object is given by
a = gsinθ/(1 + I/MR²) where θ = angle of slope = 4, I = moment of inertia of basketball = 2/3MR²
a = 9.8 m/s²sin4(1 + 2/3MR²/MR²)
= 9.8 m/s²sin4(1 + 2/3)
= 9.8 m/s²sin4 × (5/3)
= 1.14 m/s²
To find its speed v after rolling for 60 m, we use
v² = u² + 2as where u = initial speed = 0 (since it starts from rest), s = 60 m
v = √(u² + 2as) = √(0² + 2 × 1.14 m/s × 60 m) = √136.8 = 11.7 m/s
Answer:
d. 3332.5 [N]
Explanation:
To solve this problem we will use newton's second law, which tells us that the sum of forces is equal to the product of mass by acceleration.
Here we have two forces, the force that pushes the car to move forward and the friction force.
The friction force is equal to the product of the normal force by the coefficient of friction.
f = N * μ
f = (m*g) * μ
where:
N = weight of the car = 2150*9.81 = 21091.5 [N]
μ = 0.25
f = (21091.5) * 0.25
f = 5273 [N]
Now as the car is moving forward, the car wheels move clockwise. The friction force between the wheels of the car and the pavement must be counterclockwise, i.e. counterclockwise. Therefore the direction of this force is forward. This way we have:
F + f = m*a
F + 5273 = 2150*4
F = 8600 - 5273
F = 3327 [N]
Therefore the answer is d.
Answer: Macroscoptic Output
Explanation:
Answers to the rest:
1. B) macroscopic outputs.
2.A) a microscopic change creating a macroscopic output
3.B) Because the energy levels of the electrons in different metals are usually not the same, different metals usually emit different colors of visible light.
4.A) Heat is applied to a solid, causing its molecules to move quickly.
5.A) strontium, sodium, copper, potassium
Since nuclear fusion in the sun creates energy from matter, Einstein's formula E=mc² states that matter and energy are equal.
To find the answer, we have to know more about the nuclear fusion.
<h3>What is
nuclear fusion?</h3>
- We are aware that the sun can achieve nuclear fusion by the fusion of hydrogen atoms.
- These atoms need to get closer to one another in order to fuse.
- Since both protons inside each nucleus are positively charged, they attempt to repel one another as they get closer to one another.
- If this issue cannot be solved, nuclear fusion in the sun cannot occur.
Thus, we can conclude that, since nuclear fusion in the sun creates energy from matter, Einstein's formula E=mc² states that matter and energy are equal.
Learn more about nuclear fusion here:
brainly.com/question/25663405
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