When a high-mass star explodes, which of the following is left over in the center?

How would the gravitational force between the earth and the moon change if the moon had half the mass?

Vikki [24]

The moon's gravity, combined with the waltz of Earth and the moon around their center of mass, forces the oceans into an oval shape, with two simultaneous high tides. ... If the moon were half its mass, then the ocean tides would have been correspondingly smaller and imparted less energy to it.

5 0

3 years ago

Jamie decides to drop an egg that has a mass of 345 g off the top of a 8.2 m building. How fast will it be falling right before

zlopas [31]

Answer:

13 m/s

Explanation:

Given:

Δy = 8.2 m

v₀ = 0 m/s

a = 9.8 m/s²

Find: v

v² = v₀² + 2aΔy

v² = (0 m/s)² + 2 (9.8 m/s²) (8.2 m)

v = 12.7 m/s

Rounded to two significant figures, the speed is 13 m/s.

3 0

2 years ago

When the displacement in SHM is equal to 1/4 of the amplitude xm, what fraction of the total energy is (a) kinetic energy and (b

Anna71 [15]

Answer:

$\frac{KE}{TE} = \frac{15}{16}$

b)

$\frac{U}{TE} = \frac{1}{16}$

Explanation:

Let the amplitude of SHM is given as A

so the total energy of SHM is given as

$E = \frac{1}{2}kA^2$

now we know that

a)

kinetic energy is given as

$KE = \frac{1}{2}k(A^2 - x^2)$

here

$x = \frac{A}{4}$

so now we have

$KE = \frac{1}{2}k(A^2 - \frac{A^2}{16})$

$KE = \frac{15}{32}kA^2$

now its fraction with respect to total energy is given as

$\frac{KE}{TE} = \frac{15}{16}$

b)

Potential energy is given as

$U = \frac{1}{2}kx^2$

so we have

$U = \frac{1}{32}kA^2$

so fraction of energy is given as

$\frac{U}{TE} = \frac{1}{16}$

7 0

3 years ago

Sperm whales, just like bats, use echolocation to find prey. A sperm whale’s vocal system creates a single sharp click, but the

Tamiku [17]

Answer: The size of the whale can be estimated by using echo Sounder or Sonar

Explanation:The researchers and physicst uses the knowledge of reflection of sound in water or echo to solve a lot of puzzle under water , including calclulating the distance and size of objects like fish,sunk ship,etc

The sonar is able to receive the signals from the whales and the succesive echoes that follows when placed in a strategic position in the water in the path of the whale .

The sonar has a traducers which has both a transmitter and a receiver,so it receives pulses from the whale and transmit back same echo back to the whale and to the bottom of the sea.

Using the speed of sound underwater and time taken for succesive echoes of pulses ,it can calculate with the precision the location of the whale while the image of the whale is also capture by the traducers to determine the size.

3 0

3 years ago

Ecosystem services ____.

stepan [7]

Answer:

c) are economically valuable services provided by natural systems is the correct answer.

Explanation:

Ecosystem services are methods that happen in an ecosystem.

Ecosystem services are the abundance of advantages that nature gives to society and humankind.

Ecosystem services make the individual life pleasant via producing nutritious food and cleaned water, controlling disease, oxygen generation, soil formation, biomass production and giving social and spiritual advantages.

7 0

3 years ago