Let
be the average acceleration over the first 2.46 seconds, and
the average acceleration over the next 6.79 seconds.
At the start, the car has velocity 30.0 m/s, and at the end of the total 9.25 second interval it has velocity 15.2 m/s. Let
be the velocity of the car after the first 2.46 seconds.
By definition of average acceleration, we have


and we're also told that

(or possibly the other way around; I'll consider that case later). We can solve for
in the ratio equation and substitute it into the first average acceleration equation, and in turn we end up with an equation independent of the accelerations:


Now we can solve for
. We find that

In the case that the ratio of accelerations is actually

we would instead have

in which case we would get a velocity of

Average speed = (total distance covered) / (time to cover the distance)
Total distance = (80m) + (125m) + (45m) = 250 meters
Overall time = 10 minutes
Average speed = (250 meters) / (10 minutes)
<em>Average speed = 25 meters/minute </em>
Since we're only looking for average speed and not velocity, we don't care about any of the directions, and we don't need to calculate Mary's displacement.
Answer:
(a) An electric iron works on the heating effect of electric current
(b) The heating effect of an electric current is the tendency for electric current to cause the temperature of the material through which it is flowing to rise due to the resistance of the material
The heating effect, 'E', is given by the formula, E = I²·R·t
Where;
I = The current flowing
R = The resistance of the material
t = The time the material takes to heat up
(c) The values showed by Pinki here is the value of care, concern and prevention, to prevent the harmful effect of the high heat on the skin of her daughter
Explanation:
I’m sure “save” is the correct answer, as it is the only grammatically correct answer choice. Also, it is easy to save when you know what you’ll have to pay for in the future.
The grommets on your shoe (Holes through which you place the lace) act as the pulley. When you tighten at the top it restricts at the bottom and compresses around your foot.
The same can be applied to a pulley; If you have the proper set up Pulling one string causes two actions; the first being the most obvious. And the second being its effect. The Grommets of your shoe are the pulley's; while your Shoelaces are just the rope with which you operate the pulley.