Answer:
9.4 m/s
Explanation:
The work-energy theorem states that the work done on an object is equal to the change in kinetic energy of the object.
So we can write:
where in this problem:
W = -36.733 J is the work performed on the car (negative because its direction is opposite to the motion of the car)
is the initial kinetic energy of the car
is the final kinetic energy
Solving for Kf,
The kinetic energy of the car can be also written as
where:
m = 661 kg is the mass of the car
v is its final speed
Solving, we find
In component form, the displacement vectors become
• 350 m [S] ==> (0, -350) m
• 400 m [E 20° N] ==> (400 cos(20°), 400 sin(20°)) m
(which I interpret to mean 20° north of east]
• 550 m [N 10° W] ==> (550 cos(100°), 550 sin(100°)) m
Then the student's total displacement is the sum of these:
(0 + 400 cos(20°) + 550 cos(100°), -350 + 400 sin(20°) + 550 sin(100°)) m
≈ (280.371, 328.452) m
which leaves the student a distance of about 431.8 m from their starting point in a direction of around arctan(328.452/280.371) ≈ 50° from the horizontal, i.e. approximately 431.8 m [E 50° N].
Answer:
A. The athlete isn’t doing any work because he doesn’t move the weight.
Explanation:
We must remember the definition of work, which says that work is equal to the product of mass by the distance displaced. In this case, the athlete only does work when he lifts the weight from the ground to the point where he holds the weight suspended.
So when he's holding the weight, he doesn't do any work.
Answer:
true
Explanation:
i think it's true because I took a quiz on this
Answer:
it creates a gas called carbon dioxide. The gas begins to expand in the bottle and starts to inflate the balloon
Explanation:
Why does this happen? well, The faster-moving particles inside the bottle start to move faster and faster and soon they expand to fill the balloon.
