<em>Mechanical waves</em> <em>(a)</em> travel faster through a medium with greater physical density.
Electromagnetic waves travel slower through a medium with greater optical density.
Answer:
С. 30 m
Explanation:
Given the following data;
Initial velocity, U = 12m/s
Final velocity, V = 18m/s
Acceleration, a = 3m/s²
To find the distance, we would use the third equation of motion;
V ² = U² + 2aS
Substituting into the equation, we have
18² = 12² + 2*3*S
324 = 144 + 6S
6S = 324 - 144
6S = 180
S = 180/6
Distance, S = 30 meters.
In order to make any headway with this one, it might help
to know how many joules there are in one BTU, ya reckon ?
I went and looked it up on line, you're welcome.
1 BTU = 1055.06 joules .
So if you happen to have 1,152 BTU of energy,
there are 1055.06 joules in each one of them,
and the total is
(1,152 BTU) x (1,055.06 joule/BTU)
= 1,215,429.12 joules .
Scanning the choices for anything close, we notice that choice-'b'
is only about 0.006% less than my answer. So that must be the one
they're fishing for, and they must have used 1055-even for their
conversion factor.
Answer:
40
Explanation:
Mechanical advantage = effort arm / load arm
MA = 20 cm / 0.5 cm
MA = 40
Laws reflect scientific knowledge that experiments have repeatedly verified (and never falsified). Their accuracy does not change when new theories are worked out, but rather the scope of application, since the equation (if any) representing the law does not change.
