Answer:
b) N = 560 N, c) fr = 138.56 N, d) μ = 0.247
Explanation:
a) In the attachment we can see the free body diagram of the system
b) Let's write Newton's second law on the y-axis
N + T_y -W = 0
N = W -T_y
let's use trigonometry for tension
sin θ = T_y / T
cos θ = Tₓ / T
T_y = T sin θ
Tₓ = T cos θ
we substitute
N = W - T sin 30
we calculate
N = 640 - 160 sin 30
N = 560 N
c) as the system goes at constant speed the acceleration is zero
X axis
Tₓ - fr = 0
Tₓ = fr
we substitute and calculate
fr = 160 cos 30
fr = 138.56 N
d) the friction force has the formula
fr = μ N
μ = fr / N
we calculate
μ = 138.56 / 560
μ = 0.247
Answer: See explanation
Explanation:
Simple machine is a machine that has few moving parts or may also have no moving parts and they are usually used to make ones work easier. Examples include wheel and axle, wedge, pulley, lever, screw or an inclined plane.
Their advantages include:
• Less energy is required to perform a particular work.
• It makes work easier.
• It makes work faster.
• Simple machine enable one to do things that might have been difficult to achieve or do.
Explanation:
This due to thermal insulation of some of the roof.
An insulator is body is a poor conductor of heat and will require high thermal energy to cause temperature changes.
- A house with a roof that is thermally insulated will have poor heat conduction.
- Since little heat is conducted, there wont be enough thermal energy to melt the snow.
- Thermal energy is directly related to heat.
- A house that is not insulated will absorb a lot of heat.
- This will cause the snow to melt very fast.
Learn more:
Electrical conductors and insulators brainly.com/question/3874443
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After 5 seconds, the person would have travel 75 m
<h3>What is acceleration? </h3>
This is defined as the rate of change of velocity which time. It is expressed as
a = (v – u) / t
Where
- a is the acceleration
- v is the final velocity
- u is the initial velocity
- t is the time
<h3>How to determine the final velocity</h3>
We'll begin by obtaining the final velocity of the person. This can be obtained as follow:
- Initial velocity (u) = 10 m/s
- Acceleration (a) = 2 m/s²
- Time (t) = 5 s
- Final velocity (v) = ?
a = (v – u) / t
2 = (v – 10) / 5
Cross multiply
v – 10 = 2 × 5
v – 10 = 10
Collect like terms
v = 10 + 10
v = 20 m/s
<h3>How to determine the distance travelled</h3>
The distance travelled can be obtained as follow:
- Initial velocity (u) = 10 m/s
- Final velocity (v) = 20 m/s
- Acceleration (a) = 2 m/s²
- Distance (s) = ?
v² = u² + 2as
Collect like terms
2as = v² - u²
Divide both sides by 2a
s = (v² - u²) / 2a
s = (20² - 10²) / (2 × 2)
s = 75 m
Thus, the distance travelled by the person is 75 m
Learn more about velocity:
brainly.com/question/3411682
Learn more about acceleration:
brainly.com/question/491732
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