Online Activity in General Physics 1

A tired squirrel (mass of approximately 1 kg) does push-ups by applying a force to elevate its center-of-mass by 5 cm to do a mere 0.50 Joule of work. If the tired squirrel does all this work in 2 seconds, then determine its power.

• 0.10 Watts
• 1.00 Watts
• 0.25 Watts
• 0.50 Watts

When doing a chin-up, a physics student lifts her 42.0-kg body a distance of 0.25 meters in 2 seconds. What is the power delivered by the student’s biceps?

• 30.5 W
• 75.0 W
• 51.5W

• 100.0 W

An escalator is used to move 20 passengers every minute from the first floor of a department store to the second. The second floor is located 5.20 meters above the first floor. The average passenger's mass is 54.9 kg. Determine the power requirement of the escalator to move this number of passengers in this amount of time.

• 463 W

• 530 W

• 933 W

• 1132 W

A weightlifter lifts a barbell weighing 150 kg a distance of 1.5 meters in 3 seconds. Calculate the power exerted by the weightlifter during this lift.

• 420 W

• 525 W

• 630 W

• 735 W

A roller coaster descends from a height of 30 meters and carries 10 passengers, each with an average mass of 70 kg. What is the minimum power required to lift the roller coaster back to the original height in 60 seconds?

• 3500 W

• 4000 W

• 4200 W

• 4500 W

A cat weighing 4 kg jumps to a height of 1 meter in 0.5 seconds. Determine the power output of the cat during the jump.

• 32 W

• 40 W

• 50 W

• 60 W

A 90-kg cyclist is riding at a speed of 40 km/h. What is the cyclist's kinetic energy?

• 4550.0 J

• 5550.0 J

• 6550.0 J

• 7550.0 J

A 65-kg sprinter runs at a top speed of 27 km/h. What is the sprinter's kinetic energy?

• 1000 J

• 1500 J

• 1800 J

• 2100 J

A rocket has a mass of 1500 kg and can generate a kinetic energy of up to 9,000,000 Joules during takeoff. What is its velocity upon launch?

• 77.25 m/s

• 109.50 m/s

• 138.75 m/s

• 201.95 m/s

A 1200-kg jet has a kinetic energy of 5,400,000 Joules upon takeoff. What is the jet's velocity at takeoff?

• 65.30 m/s
• 120.70 m/s

• 94.90 m/s

• 80.50 m/s