Answer:
a) x = (0.0114 ± 0.0001) in
, b) the number of decks is 5
Explanation:
a) The thickness of the deck of cards (d) is measured and the thickness of a card (x) is calculated
x = d / 52
x = 0.590 / 52
x = 0.011346 in
Let's look for uncertainty
Δx = dx /dd Δd
Δx = 1/52 Δd
Δx = 1/52 0.005
Δx = 0.0001 in
The result of the calculation is
x = (0.0114 ± 0.0001) in
b) You want to reduce the error to Δx = 0.00002, the number of cards to be measured is
#_cards = n 52
The formula for thickness is
x = d / n 52
Uncertainty
Δx = 1 / n 52 Δd
n = 1/52 Δd / Δx
n = 1/52 0.005 / 0.00002
n = 4.8
Since the number of decks must be an integer the number of decks is 5
Answer:
200 N
Explanation:
Given that,
A ball traveling at 15 m/s hits a bat with a force of 200 N.
We need to find the force that the bat moving at 20 m/s hit the ball with.
We know that, this probelm is based on Newton's third law of motion. The force that the ball exerting on bat should be equal to the force that the bat exerting in the ball but in opposite direction.
It would mean that the ball hits the ball with a force of 200 N. Hence, the correct option is (a).
Answer:
The last graph.
Explanation:
Gravitational potential energy is the energy possessed by a body at a given height from the Earth's surface.
The formula to find the gravitational potential energy is given as:

Where, 'U' is the gravitational potential energy.
'm' is the mass of the body.
'g' is the acceleration of the body due to gravity.
'h' is the height of the body above the Earth's surface.
So, from the above equation, it is clear that, gravitational potential energy is directly proportional to the height. So, as height increases, the gravitational potential energy increases. At the surface of Earth, where, height is 0, the gravitational potential energy is also zero.
Therefore, the correct graph is a straight line with positive slope and passing through the origin. So, the last option is the correct one.