The 2nd Law says F=ma, where F is the force in Newtons, m is mass and a is acceleration. Earth's gravity is an acceleration, 9.8m/s^2. So you can solve the equation for mass, m=F/a, or m=F/9.8 where you've measured the force (weight) in Newtons.
A vaccum unlike sound,light can travel through any matter including a great vacuum of nothing (space)
The wall exerts a force of equal magnitude but in the opposite direction. So the force by the wall is 10 N to the right.
Answer:
The image distance is 20.0 cm.
Explanation:
Given that,
Power = 1.55 dp
Distance between book to eye = 26.0+3.00=29.0 cm
We need to calculate the focal length
Using formula of focal length

Put the value into the formula



We need to calculate the image distance
Using lens formula


Put the value into the formula



Hence, The image distance is 20.0 cm.
I'm actually going ahead in the book (DC Circuits) so this isn't really homework but I figured the tag was appropriate....the name of the chapter is Ohm's Law and Watt's Law.
<span>Problem: Calculate the power dissipated in the load resistor, R, for each of the circuits.Circuit (a): V = 10V; I = 100mA; R = ?; Since I know
V and
I use formula
P = IV: P = IV = (100mA)(10V) = 1 W.</span>
The next question is what I'm not sure about:
Question: What is the power in the circuit (a) above if the voltage is doubled? (Hint: Consider the effect on current).
What I did initially was: P = IV = (100mA)(2V) = 2 W
But then I looked at the answer and it said 4 W, then I looked at the Hint again. Then I remembered in the book early on it said "If the voltage increases across a resistor, current will increase."
So question is: When solving problems I have to increase (or decrease) current (I) every time voltage (V) is increased (decreased) in a problem, right? How about the other way around, when increasing current (I), you need to increase voltage (V). I'm pretty sure that's how they got 4 W, but want to make sure before I head to the next section of the book.
P = IV = (200mA)(2V) = 4 W