Answer:
56 kg
Explanation:
The change in potential energy of the man is given by:
where
m is the man's mass
g is the gravitational acceleration
is the change in height of the man
In this problem, we have:
is the gain in potential energy
g = 9.8 m/s^2 is the gravitational acceleration
is the change in height
Re-arranging the equation and substituting the numbers, we find the mass:
Average speed=total distance traveled/time. Total distance=the sum of the two short distances=79*2+77*3=389 km. Total time used to travel is 2+3=5 hr. Average speed is 389/5=77.8 km/hr.
Answer:
The momentum of an object is defined as the mass of the object times the velocity of the object, as P = m*v.
So the equipment needed would be:
Something to measure the mass of the object, like a balance.
Something to measure the speed of the object, like a doppler radar, or a simpler thing may be a cronometer, with that you can measure the amount of time that the object needs to travel a given distance, and with that you can obtain the speed of the object.
Now you can notice that speed is different than velocity, this is true, velocity is a vector, so this has a direction, then you need something to fix the direction in which the object moves, in this way you can determine the velocity.
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
The velocity of the boy when he hits the water at the bottom of the slide is 14 m/s.
<h3>
Velocity of the boy at the bottom of the slide</h3>
The velocity of the boy when he hits the water at the bottom of the slide is calculated from the principle of conservation of energy.
K.E = P.E
¹/₂mv² = mgh
v² = 2gh
v = √2gh
where;
- h is height of the boy
- g is acceleration due to gravity
v = √(2 x 9.8 x 10)
v = 14 m/s.
Thus, the velocity of the boy when he hits the water at the bottom of the slide is 14 m/s.
Learn more about velocity here: brainly.com/question/6504879
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