lab 10- Work and power

Purpose:

Determine the output power of human beings to understand the calculation for work and power.

Introduction:

Power is the rate at which work is done. To calculate the average power, we need to get the work and the time. First of all, we should lift a known mass up by a measured distance. By getting timed, we can derive the power. Then walk up the floor and get timed. We can derive the second power by using those data. Run up the floor and get timed to derive the third power.

Calculation:

As plotted.

Conclusion:

a) in your analysis we neglected KE in calculating the total work you did. Make a reasonable estimate of how big of an error this introduces into results.

b) A microwave on oven typically has a power consumption of appoximarly 1100W. How many of the flights of stair we used in this lab would you have to climb each second to equal the power output?

P=111.78w n=1100/111.78=9.84

c) W=1100*360=396000 J

d) (1) P=W/t=20833.33 watts

(2) n=P/P0=208 people

(3) W/P0=t=125000 s

Comments

Lab 19: PHYS 4A Lab--Conservation of Energy/Conservation of angular momentum

lab 6- Propagated Uncertainty in Measurements

Propagated Uncertainty in Measurements Purpose Learn how to calculate propagated uncertainty in density measurements with different metal material cylinders. Process First, we need to measure the density of two cylinders made of different materials . To measure the density we should measure its mass m, diameter d and height h. Mass(g) Diameter(cm) Height(cm) 69.4 1.55 5.01 27.6 1.59 4.98 So the density of the first material is about 7.31 g/cm^3, which may be zine. The density of the second material is about 2.80 g/cm^3, which may be aluminum. Then we should calculate the propagated uncertainty of the density. For a cylinder, its density can be calculate with the equation p=(4/∏)* [m/(d2*h)]. The differential form of this equation is dp= (∂p/∂m)*dm + (∂p/∂d)*dd + (∂p/∂h)dh, which equals to The calculation is attached below. Conclusion In this lab, we learnt ho...

Lab 22 Physical Pendulum Lab

Lab 20 Purpose: Predict an expression for the period of various physical pendulums. Verify the predicted value with the value getting from experiment. Learn to find out a physical pendulum’s period by calculating and by Logger Pro and video camera. Theory: In the first part, we need to get the center of mass of different shapes so that we can determine the momentum of inertia of them at the center of mass. By parallel axis theorem, we can derive the momentum of inertia of them at required center. Use the T=I α where α=ω^2*Θ to get the ω . And 2 π / ω is the result we want. We assume the parameter B as the base and H as height for an isosceles-triangle. When it comes to the semicircle, we use R stands for the radius of the semicircle. The result of each physical pendulums is followed. We will use Logger Pro for the experiment part to determine the period in the videos. ...

Phys4AS17 jsong

Search This Blog