Answer:
D
friction acts in the opposite direction of motion but does not affect the motion of the object
Answer:
For the complete question provided in explanation, if the elevator moves upward, then the apparent weight will be 1035 N. While for downward motion the apparent weight will be 435 N.
Explanation:
The question is incomplete. The complete question contains a velocity graph provided in the attachment. This is the velocity graph for an elevator having a passenger of 75 kg.
From the slope of graph it is clear that acceleration at t = 1 sec is given as:
Acceleration = a = (4-0)m/s / (1-0)s = 4 m/s^2
Now, there are two cases:
1- Elevator moving up
2- Elevator moving down
For upward motion:
Apparent Weight = m(g + a)
Apparent Weight = (75 kg)(9.8 + 4)m/s^2
<u>Apparent Weight = 1035 N</u>
For downward motion:
Apparent Weight = m(g - a)
Apparent Weight = (75 kg)(9.8 - 4)m/s^2
<u>Apparent Weight = 435 N</u>
Answer: 
Explanation:
The density
of a material is given by:
(1)
Where:
is the mass of the cube
is the volume of the cube
Now, the volume of a cube is equal to the length
of its edge to the power of 3:
(2)
If we know
, the volume of this cube is:
(3)
Substituting (3) in (1):
(4)
This is the density of the cube
The correct answer would be A "<span>A light-year is the distance light travels in a year.
This is considered a unit of distance connected to the distance that light can travel in one year. It is proved that light travels at 300,000 km per second so, in 1 year, it might travel 10 trillion km.
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