Answer:
K = 960 J
Explanation:
Given that,
Mass of a child = 20 kg
Mass of a sled = 10 kg
Speed of child on sled = 8 m/s
We need to find the kinetic energy of the sled with the child.
The total mass of child and the sled = 20 kg + 10 kg
= 30 kg
The formula for the kinetic energy of an object is given by :
Hence, the kinetic energy of the sled with the child is 960 J.
Explanation:
Below is an attachment containing the solution.
Yes
momentum=mass x velocity
or you could rearrange the formula to find velocity = momentum/mass (you get this by dividing both sides in the original equation by mass)
you could also get that mass= momentum/velocity (you get this by rearranging both sides of the original equation by velocity)
We are given the following:
Bobo's swimming speed = 2.0 m/s
Width of the river = 100 m
Flowrate of the river = 6.0 m/s due east
First, we need to illustrate the problem. Draw the river with a width of 100 meters. Then, the flow of the river, east at 6 meters per second. Lastly, draw Bobo at one side of the river facing north and an arrow representing swimming speed at 2 meters per second.
Now, we can use the Pythagorean theorem to solve this rate problem.
c^2 = a^2 + b^2
c = speed of Bobo needed
a = speed of Bobo facing north
b = flow rate of the river going east
c^2 = 2^2 + 6^2
c = 6.32 m / s should be his speed to overcome the current and make a landing at the desired location.
The momentum of an object is given by:
where
p is the momentum
m is the mass
v is the velocity of the object
The ball in our problem has a mass of m=1.0 kg and a momentum of
, therefore we can use the previous formula to find its velocity:
