Answer:
uk = 0.25
Explanation:
Given:-
- An object comes to stop with acceleration, a = -2.45 m/s^2
Find:-
What is the coefficient of kinetic friction between the object and the floor?
Solution:-
- Assuming the object has mass (m) that slides over a rough surface with coefficient of kinetic friction (uk). There is only Frictional force (Ff) acting in the horizontal axis on the object opposing the motion (-x direction).
- We will apply equilibrium equation on the object in vertical direction.
N - m*g = 0
N = m*g
Where, N : Contact force exerted by the surface on the floor
g : Gravitational acceleration constant = 9.81 m/s^2
- Now apply Newton's second law of motion in the horizontal ( x-direction ):
- Ff = m*a
- The frictional force is related to contact force (N) by the following expression:
Ff = uk*N
- Substitute the 1st and 3rd expressions in the 2nd equation:
uk*m*g = -m*a
uk = a / g
- Plug in the values and solve for uk:
uk = - (-2.45) / 9.81
uk = 0.25
Answer: A, C and D
Explanation:
Interference occurs when two waves superimpose to form a wave having a smaller or larger amplitude.
Constructive interference is said to occur when two waves superimpose to produce a wave having larger amplitude. It occurs for the waves having phase difference of multiple of 2π. On the other hand, destructive interference occurs for the waves having phase difference π, 3π, ..and so on.
In the given picture, the bright regions represent constructive interference where as the dark ones between them represent destructive interference. Thus, the correct letters representing constructive interference are: A, C and D.
increase because the heavier it is the more gravitational pull it has.
Answer:
D. They don't require a medium to travel through.
Explanation:
Electromagnetic waves and mechanical waves are both types of waves. Electromagnetic waves are waves that arise from the combination of electric and magnetic fields while mechanical waves are waves that arise as a result of transfer of energy via matter.
One major difference between these two types of waves is that electromagnetic waves such as light waves, radiowaves etc. do not need a medium to travel i.e. they can travel through a vacuum, while on the other hand, mechanical waves such as sound waves need a medium to travel.
Answer:
Using Disposable Chopsticks
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Using Straws
Eating Frog
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Keeping The Family Cat
Eating Farm-Raised Fish
Eating Soy
Not Finishing Your Dinner
Explanation: