Answer:
i/f = i/o + i/i f = focal, o = object, i = image
1 / i = 1 / f - 1 / o = (o - f) / o f
i = o * f / ( o - f) image distance
i = 12.5 * 22 / (12.5 - 22) = -28.9 cm
Image is real
Image is 28.9 cm to left of lens
M = - i / o = = 28.9 / 12.5 = 2.3 magnification (convex lens)
Answer:
Negative
Explanation:
Observe that the object below moves in the positive direction with a changing velocity. An object which moves in the positive direction has a positive velocity. If the object is slowing down then its acceleration vector is directed in the opposite direction as its motion (in this case, a negative acceleration).
The fatal current is 51 mA = 0.051 Ampere.
The resistance is 2,050Ω .
Voltage = (current) x (resistance)
= (0.051 Ampere) x (2,050 Ω) = 104.6 volts .
==================
This is what the arithmetic says IF the information in the question
is correct.
I don't know how true this is, and I certainly don't plan to test it,
but I have read that a current as small as 15 mA through the
heart can be fatal, not 51 mA .
If 15 mA can do it, and the sweaty electrician's resistance is
really 2,050 Ω, then the fatal voltage could be as little as 31 volts !
The voltage at the wall-outlets in your house is 120 volts in the USA !
THAT's why you don't want to stick paper clips or a screwdriver into
outlets, and why you want to cover unused outlets with plastic plugs
if there are babies crawling around.
ANSWER
C.
. newtons
EXPLANATION
According to Newton's second law,
, where
is the mass measured in kilograms.
and
is the acceleration in metres per second square.
We substitute these values to obtain,
.
We rearrange to get,
.
We multiply out the first two numbers and leave our answer in standard form to get,
.
The correct answer is C