Answer:
the first, second and fifth ones
Step-by-step explanation:
Answer:
Rolling case achieves greater height than sliding case
Step-by-step explanation:
For sliding ball:
- When balls slides up the ramp the kinetic energy is converted to gravitational potential energy.
- We have frictionless ramp, hence no loss due to friction.So the entire kinetic energy is converted into potential energy.
- The ball slides it only has translational kinetic energy as follows:
ΔK.E = ΔP.E
0.5*m*v^2 = m*g*h
h = 0.5v^2 / g
For rolling ball:
- Its the same as the previous case but only difference is that there are two forms of kinetic energy translational and rotational. Thus the energy balance is:
ΔK.E = ΔP.E
0.5*m*v^2 + 0.5*I*w^2 = m*g*h
- Where I: moment of inertia of spherical ball = 2/5 *m*r^2
w: Angular speed = v / r
0.5*m*v^2 + 0.2*m*v^2 = m*g*h
0.7v^2 = g*h
h = 0.7v^2 / g
- From both results we see that 0.7v^2/g for rolling case is greater than 0.5v^2/g sliding case.
Answer:
$301 - $397
Step-by-step explanation:
Using the Empirical rule
1) 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ .
2)95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
3)99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ .
From the above question,
Mean = 349 , standard deviation = 24.
Confidence interval = 95%
Using 2)95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
μ – 2σ
= 349 - 2(24)
= 349 - 48
= 301
μ + 2σ
349 + 2(24)
= 349 + 48
= 397
Therefore, according to the standard deviation rule, approximately 95% of the students spent between $301 and $397 on textbooks in a semester.
(a) It is leaking 18 liters per minute.
Explanation : From 15 minutes to 20 minutes, your starting point at 15 is 590 liters and at 20 you have exactly 500. Next you have 25 which is now at 410. So it's leaking 90 liters every five minutes, so of course dividing the two (90 ÷ 5) you get 18.
(a)² it increases for about the same time that it would decrease of course.
(b) The vat started at 860 liters before they started draining it.
Explanation : Well, all it takes is just working backwards, add 90 liters to the liters at 15 minutes and deduct five minutes from 15. Do this process until you arrive at 0. It's simple
