Deneb and the Sun are two stars. Deneb has a diameter that is 109-200 times greater than that of the sun. When seen from earth,

A crane is used to lower weights into a lake for an underwater construction project. Determine the tension in the cable of the c

atroni [7]

Answer:

Tension in the cable = 591292.8 N or 591.3 kN

Explanation:

Tension in the cable = Weight of object in air - upthrust/bouyancy due to the liquid

Weight of object in air = mass * acceleration due to gravity, g

Since mass is not given, it is obtained from the formula, mass = density * volume

Volume of the sphere = 4/3πr³ where r, radius = 2 m; π = 22/7

volume = 4/3 * 22/7 * (2m)³

volume of sphere = 33.52 m³

Density of concrete sphere = specific gravity * density of water

where, specific gravity = 2.8, density of water = 1000 kg/m³

density of concrete = 2.8 * 1000 kg/m³

density of concrete = 2800 kg/m³

acceleration due to gravity, g = 9.8 m/s²

Thus, weight of concrete = 2800 kg/m³ * 33.52 m³ * 9.8 m/s² = 919788.8 N

Upthrust = density of water * volume of sphere * g

Upthrust = 1000 kg/m³ * 33.52 m³ * 9.8 m/s² = 328496 N

The tension in the cable is the calculated as below;

Tension in the cable = Weight of object in air - upthrust/bouyancy due to the liquid

Tension in cable = 919788.8 N - 328.496 N = 591292.8 N

Therefore, tension in the cable is 591292.8 N or 591.3 kN

5 0

3 years ago

The Bohr model below represents which answer Choice

Anton [14]

Answer:

Na⁺

Explanation:

In the given atom:

Number of protons = 11

Number of neutrons = 12

So, the number of electrons = 10

The number of protons within an atom is used to determine the kind of atom we have been given.

Since the number of protons is the same as the atomic number, here the atomic number is 11 and this is Sodium .

In this sodium atom, the number of protons is more than the number of electrons;

Charge = number of protons - number of electrons = 11 - 10 = +1

So, we have a Na⁺

4 0

3 years ago

Solve: A car travels 2 km North , 10 km East, then 3 km West. pythagorean theorem

Evgen [1.6K]

________b_____ 7 km east

|

| 2km north.

|a

|

°

pythagorean theorem : ✓a² + b² = c²

c² = a² + b² = 4 + 49 = 53

c = ✓53 km

displacement = c = ✓53 km

distance = 10 + 3 + 2 = 15 km

5 0

3 years ago

In the child's game of tetherball, a rope attached to the top of a tall pole is tied to a ball. Players hit the ball in opposite

Eddi Din [679]

Answer:

option C

Explanation:

the ball is moving circular around the pole

Angular momentum of the system is constant

J = I ω

now,

$\omega\ \alpha\ \dfrac{1}{I}$

$\omega\ \alpha\ \dfrac{1}{mr^2}$

$\omega\ \alpha\ \dfrac{1}{r^2}$

the rope radius is decreasing as it revolving around the pole

angular speed is inversely proportional to radius.

so, the angular speed will increase.

The correct answer is option C

7 0

3 years ago

The valu

natulia [17]

Answer:

$\% Error = 2.6\%$

Explanation:

Given

$x: 1.54, 1.53, 1.44, 1.54, 1.56, 1.45$

Required

Determine the percentage error

First, we calculate the mean

$\bar x = \frac{\sum x}{n}$

This gives:

$\bar x = \frac{1.54+ 1.53+ 1.44+ 1.54+ 1.56+ 1.45}{6}$

$\bar x = \frac{9.06}{6}$

$\bar x = 1.51$

Next, calculate the mean absolute error (E)

$|E| = \sqrt{\frac{1}{6}\sum(x - \bar x)^2}$

This gives:

$|E| = \sqrt{\frac{1}{6}*[(1.54 - 1.51)^2 +(1.53- 1.51)^2 +.... +(1.45- 1.51)^2]}$

$|E| = \sqrt{\frac{1}{6}*0.0132}$

$|E| = \sqrt{0.0022}$

$|E| = 0.04$

Next, calculate the relative error (R)

$R = \frac{|E|}{\bar x}$

$R = \frac{0.04}{1.51}$

$R = 0.026$

Lastly, the percentage error is calculated as:

$\% Error = R * 100\%$

$\% Error = 0.026 * 100\%$

$\% Error = 2.6\%$

4 0

3 years ago