A toy boat moves horizontally in a pond. The horizontal position of the boat in meters over time is shown below.

The modern periodic table is arranged in order of increasing atomic

tankabanditka [31]

The periodic table is in increasing atomic mass. Hope this helped.

7 0

3 years ago

Two cars having different weights are traveling on a level surface at different constant velocities. Within the same time interv

GuDViN [60]

I think you're saying that once you start pushing on the cars, you want to be able to stop each one in the same time.

This is sneaky. At first, I thought it must be both 'c' and 'd'. But it's not
kinetic energy, for reasons I'm not ambitious enough to go into.
(And besides, there's no great honor awarded around here for explaining
why any given choice is NOT the answer.)

The answer is momentum.

Momentum is (mass x speed). Change in momentum is (force x time).

No matter the weight (mass) or speed of the car, the one with the greater
momentum is always the one that will require the greater (force x time)
to stop it. If the time is the same for any car, then more momentum
will always require more force.

4 0

3 years ago

A circular loop with radius r is rotating with constant angular velocity ω in a uniform electric field with magnitude E. The axi

inn [45]

Answer:

$\Phi_{E} = E\pi r^2 \omega t$

Explanation:

The electric flux is defined as the multiple of electric field and the area that the electric field passes through, such that

$\Phi_{E} = \vec{E}\vec{A}$

When calculating the electric flux, the angle between the directions of electric field and the area becomes important, especially if the angle is changing with time.

The above formula can be rewritten as follows

$\Phi_{E} = EA\cos(\theta)$

where θ is the angle between the electric field and the area of the loop. Note that, the direction of the area of the loop is perpendicular to the plane of the loop.

If the loop is rotating with constant angular velocity ω, then the angle can be written as follows

$\theta = \omega t$

At t = 0, cos(0) = 1 and the electric flux through the loop is at its maximum value.

Therefore the electric flux can be written as a function of time

$\Phi_{E} = E\pi r^2 \omega t$

3 0

3 years ago

Evaporation of sweat cools the skin because

Law Incorporation [45]

Answer: c. the molecules with the highest energy evaporate first, lowering the temperature of the sample

Explanation:

The process by which liquid starts to change into vapor phase at any temperature is known as evaporation.

During evaporation , the molecules which possess higher energies escape from the upper layer into vapor phase. the molecules which escape draw energy from surroundings and thus decrease the energy of the surroundings and hence lead to decrease in temperature.

As temperature of the system is directly proportional to the energy of the system , thus decrease in energy leads to decrease in temperature.

$K.E=\frac{3RT}{2}$