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4 years ago

Which of the following is not an example of doing work?

Physics

2 answers:

Tju [1.3M]4 years ago

5 0

Maybe holding a tray in the cafeteria line

Whitepunk [10]4 years ago

5 0

Answer:

A. Holding a tray in the cafeteria line!

You might be interested in

Small college has 2523 students in 1994 and 2891 students in 1996 if the enrollment follows a linear growth pattern how many stu

alexandr1967 [171]

Since it is specified that the relationship is linear, you could think of a linear graph for this. The base year would be 1994. The first point is at (0,2523) while the second point is (2,2891). The slope would be

m = (2891 - 2523)/(2-0) = 184

The slope-intercept form is y = mx + b. Let's substitute (0,2523) to the equation such that
2523 = 184(0)+b
b = 2523

Hence, the equation of the linear graph is y = 184x + 2523. Now, at 2006, x = 2006 - 1994 = 12 years.

y = 184(12) + 2523 = 4,731 students

4 0

4 years ago

A thin ring of radius R is uniformly charged with the total positive charge Q. 1. Find the electric field at distance h right ab

Paha777 [63]

Answer:

$E_{net} = \frac{k Q h}{(R^2 + h^2)^{\frac{3}{2}}}$

Explanation:

If charge Q is uniformly distributed over the ring then for small element of the ring the charge will be given as

$dq = \frac{Q}{2\pi R} dL$

now electric field due to this small element on the axis of ring at height "h" is given as

$dE = \frac{k dq}{R^2 + h^2}$

now since this electric field is radially in the direction of joining the position of charge to the given point

so net field due to ring will be along the axis of ring

so we have

$E_{net} = \int dEcos\theta$

$E_{net} = \int \frac{k dq}{R^2 + h^2} \frac{h}{\sqrt{R^2 + h^2}}$

$E_{net} = \frac{k Q h}{(R^2 + h^2)^{\frac{3}{2}}}$

4 0

3 years ago

Explain the melting of a solid in terms of molecules and energy

Pie

When you melt a solid the heat creates energy, when you heat up molecules they will move quicker and start to somewhat break apart into a liquid structure.

4 0

3 years ago

A father (mF = 85 kg) and his daughter (mD= 45 kg) stand on a flat frozen lake of negligible friction. They hold a 14 m long r

mr Goodwill [35]

Answer:

4.84615 m

Explanation:

Here the linear momentum is conserved and it is assumed that they will meet at the center of gravity of the system.

The center of gravity is given by

$R=\frac {1}{M}\sum _{i=1}^{n}m_ir _i$

where

i = Particle

m = Mass

r = Position

n = Number of particles

The father's location is taken as reference

$R=\frac{(0\times 85)+(45\times 14)}{85+45}=4.84615\ m$

The father will be 4.84615 m from the origin.

7 0

3 years ago

A 0.5kg ball falls from a building that Is 50m high. how much kinetic energy will it have when it has fallen half way to the gro

castortr0y [4]

Calculate velocity at halfway to the ground.

vfinal = root 2ad

v = root (2*9.81m/s^2*25)

v = 69.367175234 m/s

Kinetic energy = 1/2mv^2

Kinetic energy = 1/2 * (69.367175234 m/s^s^2

Ek = 2405.9025 Joules

4 0

2 years ago