We have equation of motion , here S = displacement, u = initial velocity, t is the time taken and a is the acceleration.
In this case displacement = 160 m
Initial velocity = 30 m/s
Acceleration =
Substituting we will get
So car will take 5.33 seconds to travel 160 m.
Answer:
velocity changes over time.
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.
Answer:
Forces 1 and 2 cannot have equal magnitudes.
Force 1 exceeds force 2.
Explanation:
Numbering the given statements:
- The force of the horse pulling on the cart.
- The force of the cart pulling on the horse.
- The force of the horse pushing on the road
.
- The force of the road pushing on the horse.
- When a horse pulls a cart along a flat road starting from the state of rest, the horse applies a force on the ground in downward-back direction diagonally and as its reaction it moves forward. During this action there is also a reaction force by the road on the horse which exceeds the force of the horse on the ground and as a result the horse moves forward.
- For pulling the cart the horse applies the force on the cart in the forward direction and as a reaction the cart applies a force on the horse in the backward direction which is less than the force of the horse on the cart resulting in the forward motion of the cart along with the horse.