Section 7.2 Review En
1. Martha wakes up at 5:30 a. m. and cats a bowl of corn flakes. It's a nice
day, so she decides to ride her bicycle to work, which is uphill from her
house. It is still dark outside. Martha's bike has a small electric
generator that runs from the front wheel. She ſlips on the generator so
that her headlight comes on when she starts to pedal. She then rides her
bike to work. Draw a diagram that shows the energy transformations
that occur in this situation,
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gpe = mass x gravity constant x height or… gpe = mgh

where… mass: measured in kilograms (kg)

gravity: gravity constant on earth = 10.00 m/s2

height: measured in meters (m)

gpe: measured in joules (j) or kilojoules (kj)

how do you solve gpe?

gravitational potential energy (gpe) is the energy an object has because of its position above the. ground.

gpe = mass x gravity constant x height or… gpe = mgh.

mass:

note: to earn full marks when solving science word problems, you must show your work:

formula.

example:

given values:

mass = 0.3 kg.

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me