What work do you think is done when you carry a 20 N weight backpack for a 1000 m walk? will the work be positive, negative, or
1 answer:
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C) Total Energy = Potential Energy + Kinetic Energy
Explanation:
The total energy of a system (also called mechanical energy) is given by:
where
PE is the potential energy
KE is the kinetic energy
The two types of energy have a different origin:
- Potential energy (PE) is the energy possessed by an object due to its position. It is commonly in the form of gravitational potential energy, which is the energy due to the position of the object in the gravitational field, defined as:
where m is the mass of the system, g the acceleration of gravity, h the heigth of the object relative to the ground
- Kinetic energy (KE), which is the energy possessed by an object due to its motion. It is calculated as
where m is the mass of the system and v is its speed.
Learn more about kinetic and potential energy:
#LearnwithBrainly
Answer:
a = 7.35 ft / s²
Explanation:
For this exercise we must use the kinematics relations
x = v₀ t + ½ a t²
as the runner leaves the starting line his initial velocity is zero
x = ½ a t²
a =
let's reduce the distance to foot
x = 60 yd (3ft / 1yd) = 180 ft
let's calculate
a = 2 180 / 7²
a = 7.35 ft / s²