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The two ropes seen in FIGURE are used to lower a 255 kg piano 5.00 m from a second-story window to the ground. How much work is done by each of the three forces?

The two ropes are used to lower a 255 kg piano 5.00 m from a second-story window to the ground. How much work is done by each of the three forces?

At what speed does a 1000 kg compact car have the same kinetic energy as a 20,000 kg truck going 25 km/h?

Particle A has half the mass and eight times the kinetic energy of particle B. What is the speed ratio v_A/v_B?

FIGURE is the force-versus-position graph for a particle moving along the $x-$axis. Determine the work done on the particle during each of the three intervals $0–1$m, $1–2$m, and $2–3$m.

A $2.0$kg particle moving along the $x-$axis experiences the force shown in FIGURE. The particle’s velocity is $4.0$m/s at $x=0$m. What is its velocity at $x=2$m and $x=4$m?

A particle moving on the $x-$axis experiences a force given by $F_x=q{x}^2$ , where $q$ is a constant. How much work is done on the particle as it moves from $x=0$ to $x=d$?

A $150$ g particle at $x=0$ is moving at $2.00$ m/s in the $+x-$direction. As it moves, it experiences a force given by $F_x=(0.250N)\sin (x/2.00m)$. What is the particle’s speed when it reaches $x=3.14$ m?

A horizontal spring with spring constant $750$ N/m is attached to a wall. An athlete presses against the free end of the spring, compressing it $5.0$ cm. How hard is the athlete pushing?

A $35$-cm-long vertical spring has one end fixed on the floor. Placing a $2.2$ kg physics textbook on the spring compresses it to a length of $29$ cm. What is the spring constant?