Question

Notify Me Bookmark

(a) What is the average useful power output (in W) of a person who does 6.80×106 J of useful work in 7.60 h? W (b) Working at this rate, how long (in s) will it take this person to lift 2300 kg of bricks 1.40 m to a platform? (Work done to lift his body can be omitted because it is not considered useful output here.) s

(a) What is the average useful power output (in W) of a person who does 6.80×106 J of useful work in 7.60 h? W (b) Working at this rate, how long (in s) will it take this person to lift 2300 kg of bricks 1.40 m to a platform? (Work done to lift his body can be omitted because it is not considered useful output here.) s

Image text
(a) What is the average useful power output (in W ) of a person who does 6.80 × 10 6 J of useful work in 7.60 h ? ◻ W (b) Working at this rate, how long (in s) will it take this person to lift 2300 k g of bricks 1.40 m to a platform? (Work done to lift his body can be omitted because it is not considered useful output here.) ◻ s

Detailed Answer

0 0

Please enter your email here. You will get email when this question is answered by our tutor.

Doubtrix Logo

Problem is not yet solved!

Click on Notify me to get email when question is answered.

Join Doubtrix with 7-days free trial

  • Icon Correct & Verified Answers
  • Icon No AI-Generated Answers
  • Icon Video Solution for Difficult Questions
  • Icon Work With Experts to Reach at Correct Answers
Notify me Login Sign Up

Similar/Related Questions

(a) Calculate the force (in N) the woman in the figure below exerts to do a push-up at constant speed, taking all data to be known to three digits. (You may need to use torque methods from a later chapter.) m = 53 kg N (b) How much work (in J) does she do if her center of mass rises 0.220 m? J (c) What is her useful power output (in W) if she does 15 push-ups in 1 min? (Should work done lowering her body be included? See the discussion of useful work in Work, Energy, and Power in Humans.) W
Solution
0 0

Consider a DRAM cell that uses an internal capacitor of 20 fF; it is charged to 3.3 V when storing a ' 1 '. In this problem, ignore body effect. (A real transistor like the access transistor here, or pass transistors in switch logic, can turn off before you want it to because of body effect; this one stays on until the 20 fF capacitor is fully charged. ) (6-points) (a) When writing a ' 1 ', how long does it take for the voltage on the capacitor to rise to 95% of its final value? Assume that when it is on, the access transistor in the cell has an average resistance of 6 kΩ; assume that the inverter driving the bit line has an average pull-up resistance of 1 kΩ. Ignore the resistance and capacitance of the bit line itself. (In a real memory, wire parasitics play a big role!)? (b) Suppose that when reading, the bit line is first charged to 3.3 V. The bit line is a large piece of metal, and has a total capacitance of 500 fF. How far does the bit line drop in voltage if a ' 0 ' is read? (Hint: In circuits, you learned that charge on capacitors in parallel redistributes until the voltage is equal; assume enough time is given for the bit line to drop as far as it ever will. )? (c) Suppose that the leakage current from the cell, due to the reverse-biased diode and subthreshold MOSFET currents, is no more than 2 pA. If a signal loss on the capacitor of 0.5 V can be tolerated, how often must the DRAM cell be refreshed to ensure that no data is lost?

Solution
0 0

The swimmer shown in the figure exerts an average horizontal backward force of 75.0 N with his arm during each 1.80 m long stroke. (a) What is his work output (in J) in each stroke? J (b) Calculate the power output (in W) of his arms if he does 100 strokes per minute. W
Solution
0 0