Answer:
I think C
Explanation:
If im right give brainliest :)
Answer: 1925 joules
Explanation:
weight of man = 550 N
height climbed = 3.5m
Work = ?
Since, work is done when the man pulled his weight over the height; work is expressed as the product of weight and height climbed
i.e Workdone = 550N x 3.5m
= 1925 joules
Thus, the man did a work of 1925 joules while climbing
Answer: option c.
Explanation: 3 identical resistors can only have 3 configurations
1) all 3 resistors in series
2) all 3 resistors in parallel
3) 2 parallel resistors in series with 1 resistor.
Case 1 : all 3 resistors in series
Let us assume each of the resistor has resistance value R.
The total resistor (Rt) of 3 resistors in series is given as
Rt = R1 + R2 + R3
Since R1=R2=R3=R
Rt = R+R+R = 3R.
Case 2: all 3 resistors in parallel.
The equivalent resistance of resistors in parallel is given by the formulae below.
1/Rt = 1/R1 + 1/R2 + 1/R3
Since R1=R2=R3=R
1/Rt = 1/R + 1/R + 1/R
1/Rt = 1 +1 +1/ R
1/Rt = 3/R
3 * Rt = R
Rt = R/3
Case 3: 2 parallel resistor in series with one
First is to get the equivalent resistance of the 2 parallel resistor.
1/Rt = 1/R1 + 1/R2
But R1=R2=R
1/Rt = 1/R + 1/R
1/Rt = 1 + 1/R
1/Rt = 2/R
2 *Rt = R
Rt =R/2.
R/2 in series with R has an equivalent resistance as shown below
Rt = R/2 + R
Rt = R + 2R/2
Rt = 3R/2
Since all the possible 3 configuration are listed above and there is no other then option c ( 2R/3) is not possible to achieve
Answer:
a) 14.2sec
b) 1394m away if horizontal speed never changes
c) 9.8m/s
Explanation:
Answer:
160790 J
Explanation:
We can find the heat necessary for the ice to go from -20 degrees Celsius to 0 degrees Celsius:
Where 
is the specific heat of ice, that is the amount of heat that must be supplied per unit mass to raise its temperature in a unit.
We must calculate the latent heat of fusion required for this ice mass to change to water:
Where H=334 J/g is the specific latent heat of fusion of water, that is the amount of energy needed per unit mass of a substance at its melting point to change from the solid to the liquid state.
Then we calculate the heat necessary for the water to go from 0 degrees Celsius to 20 degrees Celsius:
Where 
is the specific heat of water, that is the amount of heat that must be supplied per unit mass to raise its temperature in a unit.
Finally the 3 results are added:
