Given that,
Mass of the stone, m = 400 g = 0.4 kg
Initial speed, u = 20 m/s
It is climbed to a height of 12 m.
To find,
The work done by the resistance force.
Solution,
Let v is the final speed. It can be calculated by using the conservation of energy.
Work done is equal to the change in kinetic energy. It can be given as follows :
So, the required work done is 32.99 J.
Answer:
The correct option is (a).
Explanation:
We know that, the E is inversely proportional to the distance as follows :
We can write it as follows :
Put all the values,
So, the correct option is (a).
Mercury's natural state is where the atoms are close to each other but are still free to pass by each other. In which state(s) could mercury naturally exist?
Liquid is the answer
Answer : The heat change of the cold water in Joules is,
Explanation :
First we have to calculate the mass of cold water.
As we know that the density of water is 1 g/mL. The volume of cold water is 45 mL.
Now we have to calculate the heat change of cold water.
Formula used :
where,
Q = heat change of cold water = ?
m = mass of cold water = 45 g
c = specific heat of water =
= initial temperature of cold water =
= final temperature =
Now put all the given value in the above formula, we get:
Therefore, the heat change of cold water is
Answer:
2.11 m/s
Explanation:
Take north to be positive and south to be negative.
Average velocity = displacement / time
v = (82 m + -44 m) / (14 s + 4 s)
v = 2.11 m/s
The velocity is positive, so it is 2.11 m/s north. The magnitude of the velocity is 2.11 m/s.