U = 0, initial velocity
t = 1.85 s, the time of flght
Assume g = 9.8 m/s² and no air resistance
If the velocity of impact is v, then
v = u + gt
v = (9.8 m/s²)*(1.85 s) = 18.13 m/s
Answer: 18.13 m/s
Yes that's a true statement. That's why grandmother put a hot water bottle to warm up her bed, and not a hot bar of steel or lead.
Answer:
<em>It will cost $20.81</em>
Explanation:
<u>Cost of Electricity</u>
The rate of the cost of electricity is usually expressed in $/KWH because the consumption of electricity is measured in Kilowatts-hour.
If a 25W porch light is on day and night for a full year, the electricity consumption is:
25W*24 H/Day*365 Day/year* 1 year=219,000 WH
converting to KWH: 219,000 WH = 219,000 /1000 KWH = 219 KWH
The rate is $0.095/KWH, thus:
The cost of electricity is 219 KWH*$0.095/KWH= $20.81
It will cost $20.81
Yes but it gets a little more complicated unfortunately. The kinematic equations work more easily when you calculate the average acceleration. If that is not possible, you will need to separate the the work into parts where the acceleration is constant. IF you have a problem where the change in acceleration is exponential you would need an integral calculation.
<em>HOWEVER</em>, Even if you are under the impression that acceleration is changing in some non-linear fashion, you are probably over thinking it a bit. Simply calculate the <em>average</em> acceleration and work with that.
If you think about it, acelleration is just an expression of the <em>rate of change</em> of velocity. If that rate of change is its self changing, then that just equates to a different rate of change in velocity, i.e a different acceleration (or average acceleration). SO just take the 'average' acceleration, knowing that there is no such thing physically.