Which of the following has least mass

If your heart is beating at 76 beats per minute what is the frequency of your heart's oscillations

PSYCHO15rus [73]

That would be a frequency of 1.2666... beats per second. This can be phrased as your heart beats at 1.27 Hz.

4 0

4 years ago

A skier of mass 82.9 kg starts from rest at the top of a frictionless incline of height 20 m. At the bottom of the incline, the

ehidna [41]

Answer: 170.67 N

Explanation:

Given

Mass of skier is $m=82.9\ kg$

Height of the inclination is $h=20\ m$

Here, the potential energy of the skier is converted into kinetic energy which is consumed by the friction force by applying a constant force that does work to stop the skier.

$\Rightarrow mgh=F\cdot x\quad \quad [\text{F=constant friction force}]\\\\\Rightarrow 82.9\times 9.8\times 20=F\cdot 95.2\\\\\Rightarrow F=\dfrac{16,248.4}{95.2}\\\\\Rightarrow F=170.67\ N$

Thus, the horizontal friction force is 170.67 N.

7 0

3 years ago

A propeller is modeled as five identical uniform rods extending radially from its axis. The length and mass of each rod are 0.77

Vikki [24]

The formula for the rotational kinetic energy is

$KE_{rot} = \frac{1}{2}(number \ of\ propellers)( I)( omega)^{2}$

where I is the moment of inertia. This is just mass times the square of the perpendicular distance to the axis of rotation. In other words, the radius of the propeller or this is equivalent to the length of the rod. ω is the angular velocity. We determine I and ω first.

$I=m L^{2}=(2.67 \ kg) (0.777 \ m)^{2} =2.07459 \ kgm^{2}$

ω = 573 rev/min * (2π rad/rev) * (1 min/60 s) = 60 rad/s

Then,

$KE_{rot} =( \frac{1}{2} )(5)(2.07459 \ kgm^{2}) (60\ rad/s)^{2}$

$KE_{rot} =18,671.31 \ J$

6 0

3 years ago

In a charging process, 1 × 10^13 electrons are removed from one small metal sphere and placed on a second identical sphere. Init

liraira [26]

Answer:

r = 0.303m

= 30.3cm

Explanation:

Given that,

The number of electrons transferred from one sphere to the other,

n = 1 ×10 ¹³e le c t r o n s

The electrostatic potential energy between the spheres,

U = − 0.061 J

The charge on an electron,

q = − 1.6 × 10 ⁻¹⁹C

The coulomb constant,

K = 8.98755 × 10 ⁹ N ⋅ m ² / C 2²

Due to the transfer of electrons, both spheres become equally and oppositely.

The charge gained by the sphere due to the excess of the electron is:

q ₁ = n q

= 1 ×10 ¹³ * − 1.6 × 10 ⁻¹⁹

= -1.6 × 10⁻⁶C

The charge left on the first sphere is =

q ₂ = -q₁ = 1.6 × 10⁻⁶C

The electric potential energy between two point charges is given by the following equation:

U = K q ₁q ₂/r

q ₁ and q ₂ are the two charges.

r is the distance between the charge and the point.

K = 8.98755 × 10 ⁹ N ⋅ m ² / C ²

we have:

-0.061 = (8.98755 × 10 ⁹ * (-1.6 × 10⁻⁶)²) / r

r = (18.41 × 10 ⁻³) / 0.061

r = 0.303m

= 30.3cm

4 0

3 years ago

The longer the time between the arrival of the P-wave and S-wave, the _______ is the epicenter.

Brrunno [24]

The longer the time between the arrival of the P-wave and S-wave, the <u>farther away</u> is the epicenter.

<h3>What is epicenter and the relation between P-wave and S-wave?</h3>

The point on the earth's surface vertically above the hypocenter (or focus), point in the crust where a seismic rupture begins is said to be epicenter.
There are two types of waves during earthquakes, they are:

P - wave
S - wave

Each seismograph records the times when the first (P waves) and second (S waves) seismic waves arrive.
From the graph, through the information, scientists can determine how fast the waves are traveling.
The longer the time between the arrival of the P-wave and S-wave, the farther away is the epicenter.

Hence, Option B is the correct answer.

Learn more about epicenter,

brainly.com/question/28136716

#SPJ1

7 0

2 years ago