9. Work & Energy

Which of the following best describes the relationship between an object's speed and its kinetic energy?

CALC An object moving in the xy-plane is subjected to the force $\vec{F}=(2xy\hat{i}+x^2\hat{j})\text{N}$, where x and y are in m. Is this a conservative force?

A Porsche 944 Turbo has a rated engine power of 217 hp. 30% of the power is lost in the engine and the drive train, and 70% reaches the wheels. The total mass of the car and driver is 1480 kg, and two-thirds of the weight is over the drive wheels. If the Porsche accelerates at a_max, what is its speed when it reaches maximum power output?

Which of the following best describes how energy conversions make a car move down the street?

Why is energy required to get an object moving from rest?

Which energy transformation primarily occurs when using an electric pencil sharpener?

How is kinetic energy different from potential energy?

What is the ultimate source of energy for most processes on $Earth$?

In the context of a moving vehicle, the total stopping time is made up of which two main components?

If you run at a constant speed of $6m/s$ for $3$ minutes, how far (in meters) will you travel?

Which of the following is an example of potential energy?

Which of the following objects possesses $kineticenergy$?

(II) Two Earth satellites, A and B, each of mass m = 950 kg, are launched into circular orbits around the Earth’s center. Satellite A orbits at an altitude of 4800 km, and satellite B orbits at an altitude of 12,600 km. What are the kinetic energies of the two satellites?

A particle of mass $m$ starts from rest at point A at height $h$ above point B. Ignoring friction and air resistance, what is the minimum speed the particle must have at point A to just reach point B?

Which statement best compares $\mathrm{potential energy}$ and $\mathrm{kinetic energy}$?