Answer:
16.8ohms
Explanation:
According to ohm's law which states that the current passing through a metallic conductor at constant temperature is directly proportional to the potential difference across its ends.
Mathematically, V = IRt where;
V is the voltage across the circuit
I is the current
R is the effective resistance
For a series connected circuit, same current but different voltage flows through the resistors.
If the initial current in a circuit is 19.3A,
V = 19.3R... (1)
When additional resistance of 7.4-Ω is added and current drops to 13.4A, our voltage in the circuit becomes;
V = 13.4(7.4+R)... (2)
Note that the initial resistance is added to the additional resistance because they are connected in series.
Equating the two value of the voltages i.e equation 1 and 2 to get the resistance in the original circuit we will have;
19.3R = 13.4(7.4+R)
19.3R = 99.16+13.4R
19.3R-13.4R = 99.16
5.9R = 99.16
R= 99.16/5.9
R = 16.8ohms
The resistance in the original circuit will be 16.8ohms
Answer:
2,500 feet (760 meters)
Explannation: <em>At about 2,500 feet (760 meters), the skydiver throws out a pilot chute, and it deploys the parachute. Its used to control the fall rate.</em>
Answer:
c. 1600J
Explanation:
The loss in potential energy of the boy is given by:
![U=mg \Delta h](https://tex.z-dn.net/?f=U%3Dmg%20%5CDelta%20h)
where
m = 40 kg is the mass of the boy
g = 9.8 m/s^2 is the acceleration of gravity
is the total change in the height of the boy (4 metres + 2 cm due to the compression of the spring)
Substituting, we find
![\Delta U = (40 kg)(9.8 m/s^2)(4.02 m) = 1577 J \sim 1600 J](https://tex.z-dn.net/?f=%5CDelta%20U%20%3D%20%2840%20kg%29%289.8%20m%2Fs%5E2%29%284.02%20m%29%20%3D%201577%20J%20%5Csim%201600%20J)
Answer:
354200J
Explanation:
Given parameters:
Mass of copper bushing = 8kg
Initial temperature = 25°C
Final temperature = 140°C
Unknown:
Quantity of heat required to heat this mass = ?
Solution:
The amount of heat required to heat mass from one temperature to another is given by;
H = m c Δt
where m is the mass
c is the specific heat
Δt is the change in temperature
C is a constant and for copper, its value is 385J/kg°C
Input the parameters;
H = 8 x 385 x (140 - 25) = 354200J
Answer:elastic energy i believe
Explanation: