A nail is hit with a hammer. Which type of contact force has been applied?

Which of the following statements is true?

rosijanka [135]

The correct answers would be B, and d

3 0

3 years ago

Read 2 more answers

Explain the changes in energy as a ball is held in the air , and then dropped

Nostrana [21]

Answer:

Potential Energy to Kenetic Energy

Explanation:

When holding a ball in the air, the ball has potential energy. Once you drop the ball, the ball gains Kenetic Energy

3 0

3 years ago

A NASA satellite has just observed an asteroid that is on a collision course with the Earth. The asteroid has an estimated mass,

Citrus2011 [14]

Answer:

v = 7934.2 m/s

Explanation:

Here the total energy of the Asteroid and the Earth system will remains conserved

So we will have

$-\frac{GMm}{r} + \frac{1}{2}mv_0^2 = -\frac{GMm}{R} + \frac{1}{2}mv^2$

now we know that

$v_0 = 660 m/s$

$M = 5.98 \times 10^{24} kg$

$m = 5 \times 10^9 kg$

$r = 4 \times 10^9 m$

$R = 6.37 \times 10^6 m$

now from above formula

$GMm(\frac{1}{R} - \frac{1}{r}) + \frac{1}{2}mv_0^2 = \frac{1}{2}mv^2$

now we have

$2GM(\frac{1}{R} - \frac{1}{r}) + v_0^2 = v^2$

now plug in all data

$2(6.67 \times 10^{-11})(5.98 \times 10^{24})(\frac{1}{6.37 \times 10^6} - \frac{1}{4 \times 10^9}) + (660)^2 = v^2$

$v = 7934.2 m/s$

5 0

3 years ago

The current in a single-loop circuit with one resistance R is 6.3 A. When an additional resistance of 3.4 Ω is inserted in serie

Dmitry [639]

Answer:

10.15Ω

Explanation:

From ohm's law,

V = IR...................... Equation 1

Where V = Voltage, I = current, R = resistance.

Assume the voltage across the resistance = V,

Given: I = 6.3 A

Substitute into equation 1

V = 6.3R.................. Equation 2

When an additional resistance of 3.4 Ω is inserted in series with R,

The voltage remain the same, but the current changes

Total Resistance(Rt) = (R+3.4)Ω, I' = 4.72 A

Also from ohm' law,

V = I'Rt............... Equation 3

Substitute the value of I' and Rt into equation 3

V = 4.72(R+3.4)............... Equation 5.

Divide equation 2 by equation 5

V/V = 6.3R/4.72(R+3.4)

1 = 1.335R/(R+3.4)

R+3.4 = 1.335R

3.4 = 1.335R-R

3.4 = 0.335R

R = 3.4/0.335

R = 10.15Ω

6 0

3 years ago

Read 2 more answers

Identify and define the four major forms of matter, explain how melting, freezing, boiling,

mina [271]

There are four forms of matter: Solid, Liquid, gas and Plasma and matter undergoes various state changes termed as melting, freezing, boiling, evaporation, condensation, sublimation and deposition.

Explanation:

Solids

A matter that have a definite shape because of its closely packed molecular structure; are known as Solids. It can be identified as they have a definite shape and cannot flow or float without external forces are applied.

Liquids

These have a an internal molecular structure with comparatively more spaces with one another. Liquids have a property to flow and change shape according to the container it is taken.

Gases

The internal molecular structure of gases has the widest range of space among one another and thus they have a floating property because of least density.

Plasma

A complete ionized gas which has equal amount of positively and negatively charged ions. The best example of plasma is a plasma-ball.

Phase transformation among the four forms of matter

Melting

A matter changing from a solid phase to liquid phase is known as melting. Ex: Ice into water

Freezing

A matter changing from liquid to solid is known as freezing.

Boiling

When the liquid is heated to its boiling point, this gets transformed into the state of gas where liquid's pressure equals to the external pressure.

Evaporation

Once the liquid reached the temperature range above the boiling point ad starts converting into vapours or gaseous state.

Condensation

When the gases changes from the gaseous phase to liquid phase, this is called condensation.

Sublimation

The change of solid into gas is called as sublimation.

Deposition

Deposition refers the thermodynamic process where phase transition takes place as the gas solidifies without passing through the liquid phase. An example: the process of converting water vapour from frozen air directly into ice without initially becoming a liquid.

3 0

3 years ago