Alternating currents change direction, flowing first one way and then the other
Direct currents flow in one direction only, and are constant in time
Explanation:
Given parameters:
Weight of Ben = 600N
Weight of Dan = 600N
Distance of pull-up = 0.5m
Unknown:
Work done by each pull - up = ?
Solution:
Work done is defined as the product of the force applied to move a body through a certain distance.
Work done = Force x distance
Work done by Ben And Dan will be the same:
Work done = 600 x 0.3 = 180J
Work done by Ben = 180J
Work done by Dan = 180J
learn more:
Work done brainly.com/question/9100769
#learnwithBrainly
Answer:
a) 201.11minutes
b) 223.75minutes
Explanation:
Heat energy is defined as the energy required to change the temperature of a substance by 1kelvin.
It is expressed as H = mc∆t where m is the mass of the water
c is the specific heat capacity of the water/ice
∆t is the change in temperature
Total heat required to melt the ice
H = mLice + mc∆t
Lice is the latent heat of fusion of ice
a) To calculate how much time tmelts passes before the ice starts to melt, we will only calculate heat energy absorb by the ice before it melts.
H = mLice
H = 0.55(334000)
H = 183,700Joules
If heat is supplied to the container at the constant rate of 900 J/minute, the time taken before the ice starts to melt will be:
t = 183700/900
t = 201.11minutes
b) To calculate how much time trise does it take before the temperature begins to rise above 0°C, we will calculate the total energy absorbed at 0°C first.
H = 0.55(334000) + 0.55(2100)(0-(-15.3)
Note that the ice melts at 0°C which will be the final temperature
H = 183700+17671.5
H = 201,371.5Joules
Since heat is supplied to the container at the constant rate of 900 J/minute
900Joules = 1minute
201,371.5Joules= x
900x = 201,371.5
x = 201,371.5/900
x =223.75minutes
The time taken before the temperature begins to rise is 223.75minutes
Lose its magnetic properties
Work=force * distance
20,000 joules= 200 newtons * d
divide both sides by 200
100= distance