HELP!!!!
Which statement describes earthquakes?

They release energy.
They are caused by reduced stress in rocks.
They begin at the epicenter.
They result from movement on Earth’s surface.

The half-life of the given isotope will be 10 days, if after 30 days only 31.25 grams are remaining from a sample of 250 grams of the sample size taken in the beginning.

The Half-life is the time which is required for a quantity to reduce the content to half of the amount present as its initial value. The term is used in nuclear physics to describe how quickly an unstable atom undergo radioactive decay or how long does stable atoms survive. The term is also used generally to characterize any type of exponential decay.

The half-life of the isotope can be calculated by the formula:

FR = 0.5n

FR = Fraction Remaining = 31.25 g / 250.0 g = 0.1250

n = number of half lives elapsed = ?

0.125 = 0.5n

log 0.125 = n log 0.5

-0.9031 = -0.3010 n

n = 3.000 half lives have elapsed

3 half lives = 30 days

1 half live = 10 days

Therefore, the half-life of the isotope will be 10 days.

Learn more about Half-life here:

https://brainly.com/question/24710827

#SPJ2

Answer:

D. a plane landing on an aircraft carrier

E. rain sticking to a window

F. two train cars coupling together

Explanation:

Answer:

The answer is C

Explanation:

Scientists use creativity to determine which smaller questions are likely to yield results, imagine possible answers to their questions, and devise ways to test those answers.

Creativity is the key to make the scientific experiments more efficient and and economic and hence, a creative method can save money when you have limited resources.

A scientific method  is constituted by  a set of stages and instructions to conduct a scientific experiment to attain  a possible solution for a problem. Scientific methods have to be reproducible and effective to bring a valid solution for a hypothesis based on an observation.

Creative thinking is always paramount significance because it leads more ways and identifies the pitfalls in the available scientific methods. Creativity improves the way of designing a scientific experiments and to gather informations also.

Therefore, creative method can save money when you have limited resources is a true statement regarding a scientific method.

To find more on scientific methods, refer here:

https://brainly.com/question/7508826

#SPJ2

Answer:

[tex]0.6\; \rm m\cdot s^{-1}[/tex], assuming that drag of the water on the log is negligible.

Explanation:

The momentum [tex]p[/tex] of an object is equal to the product of mass [tex]m[/tex] and velocity [tex]v[/tex]. That is, [tex]p = m\, v[/tex].

If the drag of water on the log is negligible, momentum of the beaver and the log, combined, would be preserved.

The momentum of the beaver and the log, combined, was initially [tex]0\; \rm kg\cdot m \cdot s^{-1}[/tex].

The momentum of the beaver right after the dive would be [tex]7.5 \; {\rm kg} \times 4\; {\rm m \cdot s^{-1}} = 30\; {\rm kg \cdot m \cdot s^{-1}}[/tex].

The sum of the momentum of the beaver and the log is conserved and should continue to be [tex]0\; {\rm kg\cdot m \cdot s^{-1}}[/tex] even after the dive. Since the momentum of the beaver is [tex]30\; {\rm kg \cdot m \cdot s^{-1}[/tex] after the dive, the momentum of the log should become [tex](-30)\; {\rm kg \cdot m \cdot s^{-1}}[/tex].

Since the mass of the log is [tex]50\; {\rm kg}[/tex], the new velocity of this log would be:

[tex]\begin{aligned}v &= \frac{p}{m} \\ &= \frac{(-30)\; {\rm kg \cdot m \cdot s^{-1}}}{50\; {\rm kg}} \\ &= (-0.6)\; {\rm m \cdot s^{-1}}\end{aligned}[/tex].

(The new velocity of the log is negative because the log would be moving away from the beaver.)

The speed of an object is the magnitude of velocity. For this log, a velocity of [tex](-0.6)\; {\rm m \cdot s^{-1}}[/tex] would correspond to a speed of [tex]|(-0.6)\; {\rm m \cdot s^{-1}| = 0.6\; {\rm m \cdot s^{-1}[/tex].

Answer:

2000 J

Hope you could get an idea from here.

Doubt clarification - use comment section.

S O L U T I O N:

Here we've been provided with the information i.e

Ans we have given to find out what is work done (W) = ?

The standard formula to calculate work done is given by,

[tex]:\implies\sf{w = f \times s \times cos \theta}[/tex]

[tex]:\implies\sf{w = 20 \times 200 \times cos60}[/tex]

[tex]:\implies\sf{w = 20 \times 200 \times \frac{1}{2} }[/tex]

[tex]:\implies\sf{w = 20 \times 100 \times 1}[/tex]

[tex]:\implies\sf{w = 2000J}[/tex]

I hope it's helpful for you ☺️

1) iron

2) aluminium

3) silver

4) copper

Answer:

The conservation of momentum of a system is a fundamental principle in classical mechanics. The only condition for this principle being valid is that the system should be an isolated one, i.e. It should not be acted upon by any external force.

Answer:

2. thermal insulator. 3. convection current. 4. conduction. 5. thermal conductor. 6. radiation.

Explanation:hope this helps you.

Answer:

geosphere and hydrosphere

Explanation:

The number of variations the dealership have is 40 cars.

Data given;

This is the total numbers of cars available in the dealer shop at the moment.

To get that, we simply multiply the numbers of colors available, the number of transmission and the makes of car available.

This is equal to

[tex]4*2*5=40[/tex]

From the above calculation, we can say that the variations the dealership offers is 40

Learn more on combination here

https://brainly.com/question/10339517

Answer:

Newton's universal law of gravitation predicts how mass can distort light, so we can apply Newton's law to determine the mass of the cluster. ... The lensing allows us to determine the orbital speeds of galaxies in the cluster, so that we can determine the mass of the cluster from the orbital velocity law.

Explanation:

To make the boiler more efficient, we would replace the resistor with another double the length.

We know that the resistance of the resistor in the boiler is given by R = ρl/A where

Also, the power generated by the resistor is P = i²R where

If i is constant, we see that P ∝ R.

So, to increase the efficiency, the value of the resistance has to increase.

Also, since R = ρl/A and ρ and A are constant, we see that R ∝ l.

Since P ∝ R and R ∝ l ⇒ P ∝ l.

So, to increase the efficiency, we would double the length of the resistor.

So, to make the boiler more efficient, we would replace the resistor with another double the length.

Learn more about resistors here:

https://brainly.com/question/25209910

The velocity of the tennis ball when it hits the ground is calculated as 4.43m/s. Details about velocity can be found below.

The velocity of a moving object can be calculated using the equation of motion as follows:

v² = u² + 2as

Where;

v² = 0² + 2(9.8) (1)

v² = 19.6

v = ✓19.6

v = 4.43m/s

Therefore, the velocity of the tennis ball when it hits the ground is calculated as 4.43m/s.

Learn more about velocity at: https://brainly.com/question/18084516

#SPJ1

Answer:

The earth travels around the sun in a (parabolic) path known as the ecliptic.

The axis of the earth's rotation is tilted about 23 deg to the ecliptic.

At the winter solstice (around Dec. 21), the sun will appear to be at its farthest south in its orbit. (This marks the beginning of winter for observers in the northern hemisphere and the beginning of summer for an observer in the southern hemisphere)

The tilt of the axis of the earth's rotation causes the change in the daylight hours.

Answer:

A network has 5 basic components viz. clients, servers, channels, interface devices and operating systems.

Answer:

A perfectly elastic collision conserves momentum and kinetic energy..

Answer:

I put the answer

Explanation:

Can you see it

10Hz is the frequency of the wave.

To calculate the frequency of a wave, divide the velocity of the wave by the wavelength. Write your answer in Hertz or Hz

Given,

F = 2

λ=2m

v=20m/s

By applying the formula, we get

V = Fλ

F = V / λ

F = 20 / 2

=10Hz

Wave frequency is the number of waves that pass a fixed point in a given amount of time.

Learn more about Wave frequency here: brainly.com/question/25699025

#SPJ2

Answer:

less than.

Explanation: because Friction is the resistance to motion of one object moving relative to another. which means it cant be greater because how would it be greater if its pushing forward when friction is the resistance.

THANKS FOR THE POINTS :D

In classical mechanics, kinetic energy (KE) is equal to half of an object's mass (1/2*m) multiplied by the velocity squared. For example, if a an object with a mass of 10 kg (m = 10 kg) is moving at a velocity of 5 meters per second (v = 5 m/s), the kinetic energy is equal to 125 Joules, or (1/2 * 10 kg) * 5 m/s2.

Answer:

hi your answer should be B

Explanation:

Hope this helps!

Answer:

ionic

Explanation:

two metals that bond are considered ionic bonds

Here are all the steps.

When you are pulling a sled with constant velocity with a rope then the ground exerts a surface force on the sled will be equal to 573.56 N.

The pulling force delivered axially by a cable, string, chain, or by either end of a rod, truss member, or another such 3-D object is known as tension in physics. Tension can be described as the action-reaction pair of forces acting at each end while tension is a polar opposite of compression.

A restoring force causes tension when atoms or molecules are torn apart at the atomic level and build up potential energy.

When you are trying to move upward and push in a positive way,

F = - 112 i + 57.4 (9.8) j

F = -112 i + 562.52 j

[tex]F = \sqrt{(-112)^2+ (562.52)^2}[/tex]

[tex]F =\sqrt{12544 + 316428.7}[/tex]

F = 573.56 N

Therefore, the surface force the ground exerts on the sled is 572.52 N.

Learn more about tension, here:

brainly.com/question/15880959

#SPJ2

Answer:

1.) TABLE = The table is 2.74 m (9.0 ft) long, 1.525 m (5.0 ft) wide, and 76 cm (2.5 ft) high with any continuous material so long as the table yields a uniform bounce of about 23 cm (9.1 in) when a standard ball is dropped onto it from a height of 30 cm (11.8 in), or about 77%.

2.) TENNIS = Tennis is a racket sport that can be played individually against a single opponent (singles) or between two teams of two players each (doubles). Each player uses a tennis racket that is strung with cord to strike a hollow rubber ball covered with felt over or around a net and into the opponent's court.

3.) PING-PONG = Table tennis, also known as ping-pong and whiff-whaff, is a sport in which two or four players hit a lightweight ball, also known as the ping-pong ball, back and forth across a table using small rackets. ... Spinning the ball alters its trajectory and limits an opponent's options, giving the hitter a great advantage.

4.) NET = This is stretched across the centter of the table by a cord attached to a post at either end. It measures 6ft long and the ball must pass over it for a rally to continue.

5.) BALL = The ball, which is spherical and hollow, was once made of white celluloid. Since 1969 a plastic similar to celluloid has been used. The ball, which may be coloured white, yellow, or orange, weighs about 0.09 ounce (2.7 grams) and has a diameter of about 1.6 inches (4 cm).

6.) RACKET = A table tennis racket is made up of two distinct parts - a wooden blade which incorporates the handle together with table tennis rubbers affixed to each side of the blade using water-based glue.

Explanation:

All my answers are

about the tools of the

game of tennis

Answer:

Explanation:

Power is the rate at which work is done and can be found by using the formula

[tex]p = \frac{w}{t} \\ [/tex]

p is power in Watts ( W)

w is the workdone in J

t is time in s

From the question

w = 10,000 J

t = 4 s

We have

[tex]p = \frac{10000}{4} = 2500 \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

C.Compacting the waste and burying it in a shallow landfill.

Explanation:

It is buried in a shallow landfill because it is less reactive.

Answer:

Flow is proportional to change in pressure and inversely proportional to resistance.

Explanation:

F=k.g m\s2

=2.5 m\s2 14000k.g

= 35000N

Answer:

"electric or magnetic"

F = q E    force on charge q due to electric field E

F = q v x B       force on charge q due to magnetic field B

Answer:

the interval between transits of the apparent or mean sun across the meridian at any place.

This is because the cloth soaked in water can absorb and evaporate the heat from your forehead.

This technique is used to cool down your fever, and to help you feel better.