7)

1 answer:

8 0

Hello,

The answer is A) a mixture. An element as defined as a pure substance, that cannot be broken down and most are typically naturally occurring. A compound occurs in chemical bonding. A substance is either a pure element or compound.

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The coefficient of the restitution of an object is defined as the ratio of its outgoing to incoming speed when the object collid

IgorLugansk [536]

Answer:

48.16 %

Explanation:

coefficient of restitution = 0.72

let the incoming speed be = u

let the outgoing speed be = v

kinetic energy = 0.5 x mass x $x velocity^{2}$

incoming kinetic energy = 0.5 x m x $x u^{2}$

coefficient of restitution = $\frac{v}{u}$

0.72 = $\frac{v}{u}$

v = 0.72u

therefore the outgoing kinetic energy = 0.5 x m x $(0.72u)^{2}$

outgoing kinetic energy = 0.5 x m x $0.5184 x u^{2}$

outgoing kinetic energy = 0.5184 (0.5 x m x $x u^{2}$ )

recall that 0.5 x m x $x u^{2}$ is our incoming kinetic energy, therefore

outgoing kinetic energy = 0.5184 x (incoming kinetic energy)

from the above we can see that the outgoing kinetic energy is 51.84 % of the incoming kinetic energy.

The energy lost would be 100 - 51.84 = 48.16 %

5 0

3 years ago

On your first day at work as an electrical technician, you are asked to determine the resistance per meter of a long piece of wi

Lostsunrise [7]

Answer:

$0.06\Omega/m$

Explanation:

Firstly, when you measure the voltage across the battery, you get the emf,

E = 13.0 V

In order to proceed we have to assume that the voltmeter offers no loading effect, which is a valid assumption since it has a very high resistance.

Secondly, the wires must be uniform. So the resistance per unit length is constant (say z). Now, even though the ammeter has very little resistance it cannot be ignored as it must be of comparable value/magnitude when compared to the wires. This is can seen in the two cases when currents were measured. Following Ohm's law and the resistance of a length of wire being proportional to it's length, we should have gotten half the current when measuring with the 40 m wire with respect to the 20 m wire ( $I=\frac{V}{R}$ ). But this is not the case.