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3 years ago

The same book with a mass of 3 kg is now at rest on a bookshelf 5 meters above the ground. What is the book’s kinetic energy?

Physics

1 answer:

RoseWind [281]3 years ago

6 0

Answer:

0 J

Explanation:

Since the book is at rest then its velocity will be zero therefore

K.E=

$\frac{1}{2} m {v}^{2}$

since v=0

then

K.E= 0

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A well-insulated bucket of negligible heat capacity contains 129 g of ice at 0°C.

Luba_88 [7]

Answer:

The final equilibrium temperature of the system is $T = 12.48^oC$

For the ice it would melt completely the mass that would remain is Zero

Explanation:

In the following question we are provided with

Mass of the ice $M_{i}$ = 129 g = 0.129 kg

Mass of the steam $M_s$ = 19 g = 0.019 kg

Initial temperature is $T_i$ = 0°C

Temperature of steam $T_s$ = 100°C

Following the change of state of water in the question

The energy required by ice to change to water is mathematically given as

$Q_A = M_iL_f$

Where $L_f$ is a constant known as heat of fusion and the value is $334*10^3 J/kg$

$Q_A = 0.129 *334 *10^3 = 43086 J$

The energy been released when the steam changes to water is mathematically given as

$Q_B = M_s * L_v$

Where $L_v$ is a constant known as heat of vaporization and the value is $2256*10^3J/kg$

$Q_B = 0.019 * 2256*10^3 = 42864J$

The energy released when the temperature of water decrease from 100°C to 0°C is

$Q_C = M_s *C_water ($ 100°C)

Where $C_{water}$ is the specific heat of water which has a value $4186J/kg \cdot K$

$Q_C = 0.019 *4186*100 = 7953.4$

Looking at the values we obtained we noticed that ]

$Q_B + Q_C > Q_A$

What this means is that the ice will melt

bearing in mind the conservation of energy

looking the way at which water at different temperature were mixed according to the question

Heat lossed by the vapor = heat gained by ice

$Q_B + M_s *C_{water}(100-T) = Q_A + M_i C_{water} T$

$T = \frac{Q_B+M_s *C_{water}(100^oC)-Q_A}{(M_s *C_{water})+(M_i*C_{water})}$

$T = \frac{42864+7953.4-43086}{(0.019+0.129)(4186)}$

$T = 12.48^oC$

3 0

4 years ago

The position of a particle is given by ~r(t) = (3.0 t2 ˆi + 5.0 ˆj j 6.0 t kˆ) m

Julli [10]

Answer:

$v=(6ti+6k)\ m/s$

Explanation:

Given that,

The position of a particle is given by :

$r(t) = (3.0 t^2 i + 5.0j+ 6.0 tk) m$

Let us assume we need to find its velocity.

We know that,

$v=\dfrac{dr}{dt}\\\\=\dfrac{d}{dt}(3.0 t^2 i + 5.0j+ 6.0 tk) \\\\=(6ti+6k)\ m/s$

So, the velocity of the particle is $(6ti+6k)\ m/s$ .

5 0

3 years ago

Give two reasons why circular water waves decrease in amplitude

Ronch [10]

1. friction between water molecules
2. the wave spreads out onto a larger and larger area, so per unit area, the energy of the wave goes down

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3 years ago

Which of the following is an SI base unit for measuring mass?

Dimas [21]

Answer:

I think its Pound or a gram

8 0

2 years ago

What does a dielectric do to a capacitor?

Leto [7]

A dielectric fabric is used to split the conductive plates of a capacitor. This insulating cloth significantly determines the properties of a component. The dielectric constant of fabric determines the amount of strength that a capacitor can keep while voltage is applied.

A capacitor is an electrical component that attracts energy from a battery and stores the power. Internal, the terminals connect with metal plates separated by way of a non-engaging in substance. While activated, a capacitor quickly releases electricity in a tiny fraction of a 2d.

Capacitor, a tool for storing electric electricity, together with two conductors in near proximity and insulated from each different. A simple example of this sort of garage tool is the parallel-plate capacitor.

A capacitor is a tool that shops electric power in an electric-powered area. it is a passive digital thing with terminals. The effect of a capacitor is called capacitance.

Learn more about capacitors here brainly.com/question/13578522

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2 years ago