We will find the mass from
mass = density x volume
We are told the density and must find the volume from the dimensions given
the volume of the washer will be the area x thickness (remembering to convert all measurements to meters)
if the washer had no hole, its area would be pi (0.0225m)^2 (remember to convert to meters and to use radius)
the area of the hole is pi(0.00625m)^2
so the area of the washer is pi[(0.0225m)^2 - (0.00625m)^2] = 1.5x10^-3 m
the volume of the washer is 1.5x10^-3 m x 1.5x10^-3 m = 2.25x10^-6 m^3 (the thickness of the washer is 1.5 mm = 1.5x10^-3m)
thus, the mass of the washer = 8598kg/m^3 x 2.25x10^-6m^3 = 0.0189kg = 18.9 grams
Answer:
s is distance so it's dimensions become L.
Nd other side we have ut+1\2at^2.
as 1\2 is a constant it will have dimensions and apply the dimensions to other quantities.
on solving u will get L there also i,e ur LHS = RHS.
thus the equation is dimensionally consistent.
Explanation:
Resistance = (voltage) / (current)
Resistance = (120 V) / (0.5 A)
<em>Resistance = 240 ohms</em>
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Know what ? There might be too much information given in this question. I want to check, because it's possible that it might not even all fit together.
To calculate my answer, I only used the voltage and the current. I didn't use the "60 watts", and I'm curious to know whether it even fits with the given voltage and current.
Power = (voltage) times (current).
Power = (120 V) times (0.5 A)
Power = 60 watts
Well gadzooks and sure enough ! The three numbers given in the question all go together nicely.
And not only THAT !
The answer could have been calculated by using ANY TWO of them.
Answer:

negative sign indicates that the distance is decreasing with time
Explanation:
Let at any time t after noon that is 12 p.m.
distance traveled by car A = 40t
distance traveled by car B = 90-60t
then distance between the two cars at time t
............1
also, at time 1 p.m.
distance 
D=50 Km
differentiating equation 1 w.r.t. t we get

put t= 1 and D= 50 we get

