Answer:
The tension in the upper rope (top rope), T1 = 1,888 N
Explanation:
The Parameters that were given:
Mass A, M1 = 70kg
Mass B. M2 = 90kg
acceleration, a = 2 m/s2
Assume the rope doesn't have mass, acceleration due to gravity, g
= 9.8 m/s2
The tension, T in a platform = m (a + g)
Then the tension, T1 in the upper rope = m1 (a + g) + T2
Where T2 = Tension in the lower rope
First, we calculate T2
Since the platform accelerates upward the acceleration would be positive
T2 = m2 (a + g)
T2 = 90kg ( 2 m/s2 + 9.8 m/s2)
T2 = 1,062N
To calculate the tension T1,
T1 = m1 (a + g) + T2
= 70kg (2 m/s2 + 9.8 m/s2) + 1062N
T1 = 1,888 N
Sound waves can travel through ANY material ... solid, liquid, or gas.
The thing is: Sound NEEDS material to travel through, and if there's
nothing there, then sound can't go anywhere. The correct choice
on the list is 'D' ... Sound can't travel through vacuum, because
there's nothing there. When we talk to each other, the AIR between
us carries the sound waves.
Have you ever seen any video of two astronauts standing on the
moon, or two astronauts "space-walking" on the outside of the
Space Shuttle ?
Naturally, they have their helmets on, and they're talking to
each other. How are they talking ? No matter how close together
they are, they're talking to each other by radio ! because there's
nothing between them to carry sound. Even if they're only a few
inches apart, they can SHOUT but the other one can't hear it.
I have read ... I don't think there's any video of this ... that sometimes
when two astronauts are very close together, they can talk if they
touch their helmets together. Then the sound vibrations can go from
one helmet over to the other one, through the solid shell of the helmets.
I believe the correct answer would be zero. The work done in the truck is equal zero since the truck is not moving. Work by definition is the product of force and distance traveled due to the force. In this case, distance is zero giving us a zero work. Hope this helps.
Answer:
no, because the waves do not have the same amplitude
Explanation:
