Answer:
d. 50 C
Explanation:
In this problem, we have to add 800 ml of water at 20 Celsius to 800 ml of water at 80 Celsius.
According to the 2nd law of thermodynamics, heat transfers from hot to cold temperature.
The quantity of both the different waters is equal so this makes it very easy. All we have to do is find the mean of both the temperatures:
Final temperature = (20 C + 80 C)/2
= 50 Celsius
Answer : The power absorbed by the bulb is, 0.600 W
Explanation :
As we know that,
Power = Voltage × Current
Given:
Voltage = 3 V
Current = 200 mA = 0.200 A
Conversion used : (1 mA = 0.001 A)
Now put all the given values in the above formula, we get:
Power = Voltage × Current
Power = 3V × 0.200 A
Power = 0.600 W
Thus, the power absorbed by the bulb is, 0.600 W
Answer:
Rita and Katrina both followed similar paths into the Gulf.
Explanation:
Answer: 288.8 m
Explanation:
We have the following data:
is the time it takes to the child to reach the bottom of the slope
is the initial velocity (the child started from rest)
is the angle of the slope
is the length of the slope
Now, the Force exerted on the sled along the ramp is:
(1)
Where
is the mass of the sled and
its acceleration
In addition, if we draw a free body diagram of this sled, the force along the ramp will be:
(2)
Where
is the acceleration due gravity
Then:
(3)
Finding
:
(4)
(5)
(6)
Now, we will use the following kinematic equations to find
:
(7)
(8)
Where
is the final velocity
Finding
from (7):
(9)
(10)
Substituting (10) in (8):
(11)
Finding
:

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