Answer:
We can easily find out the beginning point of the line by using dot representation.
When it comes to position vector, it expresses the exact position of certain object from the starting point of the coordinate system.
The vector is a straight line that has a certain end which is fixed to its body.
The other end is linked with a moving point that tells an accurate position of that specific point.
Answer:
The work done on the suitcase is, W = 1691 J
Explanation:
Given data,
The force on the suitcase is, F = 89 N
The distance Russell dragged the suitcase, S = 19 m
The work done on the suitcase by Russell is equal to the work done on the suitcase to overcome the friction
The work done on the suitcase by Russell is given by the formula
W = F · S
Substituting the given values,
W = 89 N x 19 m
W = 1691 J
Hence, the work done on the suitcase is, W = 1691 J
Answer: B, increase the rate at which he turns the crank
Explanation: i got it right
Your potential energy at the top of the hill was (mass) x (gravity) x (height) .
Your kinetic energy at the bottom of the hill is (1/2) x (mass) x (speed)² .
If there was no loss of energy on the way down, then your kinetic energy
at the bottom will be equal to your potential energy at the top.
(1/2) x (mass) x (speed)² = (mass) x (gravity) x (height)
Divide each side by 'mass' :
(1/2) x (speed)² = (gravity) x (height) . . . The answer we get
will be the same for every skater, fat or skinny, heavy or light.
The skater's mass doesn't appear in the equation any more.
Multiply each side by 2 :
(speed)² = 2 x (gravity) x (height)
Take the square root of each side:
<u>Speed at the bottom = square root of(2 x gravity x height of the hill)</u>
We could go one step further, since we know the acceleration of gravity on Earth:
Speed at the bottom = 4.43 x square root of (height of the hill)
This is interesting, because it says that a hill twice as high won't give you
twice the speed at the bottom. The final speed is only proportional to the
<em>square root </em>of the height, so in order to double your speed, you need to
find a hill that's <em>4 times</em> as high.
