Answer:
Divide then multiply or multiply then divide
Explanation:
to get the answer of a and b
Answer:
Explanation:
Ohm's law states the relationship between voltage, resistance and current in an electrical circuit containing passive elements only:
where
V is the voltage supplied by the battery
R is the resistance of the circuit
I is the current
From the equation, we see that the voltage, V, is directly proportional to the current in the circuit, I.
The heat needed is given by Mcθ , where m is the mass in Kg, c is the heat capacity of aluminium, and θ is the change in temperature.
Specific heat capacity of aluminium is 0.9 j/g°c
thus; Heat = 55 × 0.9 × 72.2
= 3573.9 Joules or 3.574 kJ
Answer:
B
Explanation:
Digestive as it has enzymes that turn food into energy.
<span>1.57 seconds.
The rod hanging from the nail constructs a physical pendulum. The period of such a pendulum follows the formula
T = 2*pi*sqrt(L/g)
where
T = time
L = length of pendulum
g = local gravitational acceleration
So the problem becomes one of determining L. It's tempting to consider L to be the distance between the center of mass and the pivot, but that isn't the right value. The correct value is the distance between the pivot and the center of percussion. So let's determine what that is. We can treat the uniform thin rod as an uniform beam and for an uniform beam the distance between the center of mass and the center of percussion is expressed as
b = L^2/(12A)
where
b = distance between center of mass and center of percussion
L = length of beam
A = distance between pivot and center of mass
Since the rod is uniform, the CoM will be midway from either end, or 0.962 m / 2 = 0.481 m from the end. The pivot will therefore be 0.481 m - 0.048 m = 0.433 m from the CoM
Now let's calculate the distance the CoP will be from the CoM:
b = L^2/(12A)
b = (0.962 m)^2/(12 * 0.433 m)
b = (0.925444 m^2)/(5.196 m)
b = 0.178107005 m
With the distance between the CoM and CoP known, we can now calculate the effective length of the pendulum. So:
0.433 m + 0.178107005 m = 0.611107005 m
And finally, with the effective length known, let's calculate the period.
T = 2*pi*sqrt(L/g)
T = 2*pi*sqrt((0.611107005 m)/(9.8 m/s^2))
T = 2*pi*sqrt(0.062357858 s^2)
T = 2*pi*0.249715554 s
T = 1.569009097 s
Rounding to 3 significant figures gives 1.57 seconds.
Let's check if this result is sane. Looking up "Seconds Pendulum", I get a length of 0.994 meters which is longer than the length of 0.611 meters calculated. But upon looking closer at the "Seconds Pendulum", you'll realize that it's period is actually 2 seconds, or 1 second per swing. So the length of the calculated pendulum is sane.</span>
