Answer: be alert for pedestrians near the bus.
Explanation: Due to road accidents many Governments around the world has adopted and put in place certain rules and regulations with regards to road safety, this is so to prevent the or reduce the chances of accidents happening.
Road safety rules are rules and guidelines put in place by Government in order to prevent road accidents and maintain a free flow of traffic. An example of such rules is 'be alert for pedestrians near the bus ' when approaching a local bus that is stopped.
efficiency = (useful energy transferred ÷ energy supplied) × 100
It's easy to use this formula, but we have to know both the useful energy and the energy supplied. The drawing doesn't tell us the useful energy, so we have to find a clever way to figure it out. I see two ways to do it:
<u>Way #1:</u>
We all know about the law of conservation of energy. So we know that the total energy coming out must be 250J, because that's how much energy is going in. The wasted energy is 75J, so the rest of the 250J must be the useful energy . . . (250J - 75J) = 175J useful energy.
(useful energy) / (energy supplied) = (175J) / (250J) = <em>70% efficiency</em>
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<u>Way #2: </u>
How much of the energy is wasted ? . . . 75J wasted
What percentage of the Input is that 75J ? . . . 75/250 = 30% wasted
30% of the input energy is wasted. That leaves the other <em>70%</em> to be useful energy.
I'll go ahead and answer the ones here without an answer. For reference, the half-life formula is <em>final amount = original amount(1/2)^(time/half-life)</em>
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4) 12.5g
x = 100(1/2)^(63/21)
5) 50g
3.125 = x(1/2)^(0.1/0.025)
6) 500g
x = 4000(1/2)^(525/175)
7) 0.24g
0.06 = x(1/2)^(11430/5730)
8) 125g
x = 1000(1/2)^(17100/5700)
Hope this helps! :)
Answer:
a.) Speed V = 29.3 m/s
b.) K.E = 1931.6 J
Explanation: Please find the attached files for the solution
A) The rhino's average velocity on the x-axis is
. The position x after time t=21.5 s can be found by using the relationship:
where we used
as the x-position at time t=0, since the rhino was at the origin.
SImilarly, the average velocity on the y-axis is
, and the y-position after time t=21.5 s can be found by using:
where we used
since the the rhino was at the origin at time t=0.
b) The distance of the rhino from the origin can be calculated by calculating the resultant of the displacement of the rhino on both axes:
