KE = kinetic energy
PE = potential energy
GPE = gravitational potential energy
energy is always measured in Joules (J)
KE = (0.5) times the mass times the velocity^2
square the velocity first
Mass = (KE x 2) / v^2
square the velocity first, then double the kinetic energy, then divide
mass is measured in kg
velocity = sqrt(KE x 2 / m)
velocity can be called speed, like in the the second problem
remember to find the square root after you double the KE and divide that by the mass.
for example: if after you doubled KE and divided it by the mass you got sqrt(20), the answer would be about 4.47
GPE = mass x gravitational pull (about 9.8 m/s^2 on earth) x height
height = (PE) / (g x m)
do g x m first
So for question 1:
KE = (0.5)0.1 x 1.1^2
always square the velocity first:
KE = (0.5)0.1 x 1.21
KE = 0.0605
so if you rounded it to the nearest hundreths you would get KE = 0.06 J
don't forget the unit of energy is in Joules
Answer:
towards left
Explanation:
As we know that there is no external force on the system of two cart so total momentum of the system is conserved
so we will say
now plug in all data into the above equation
here we assumed that left direction of motion is negative while right direction is positive
so we can solve it for speed v now
Answer:
X and Z
Explanation:
Conduction occurs through direct physical contact. Heat transferred from the pot to the handle, and from the handle to the hand, are both examples of conduction.
<span>When a person lifts the block, the block has more potential energy. Therefore the person does positive work on the block.
work = m g h
work = (4.5 kg) (9.80 m/s^2) (1.2 m)
work = 52.92 joules
The person's work on the block is 52.92 joules
When the block is being raised, the force of gravity opposes the motion. Therefore the force of gravity does negative work on the block.
work = - (force) (h)
work = - m g h
work = -(4.5 kg) (9.80 m/s^2) (1.2 m)
work = -52.92 joules
The work done by the force of gravity on the block is -52.92 joules
Note that when the block is moved horizontally, the potential energy does not change. Therefore there is no work done on the block when it moves horizontally (we are assuming that the kinetic energy does not change).</span>
