All categories

3 years ago

What is the full definition of specific heat?

2 answers:

4 0

The heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).

ruslelena [56]3 years ago

3 0

Specific Heat capacity or thermal capacity is a measurable physical quantity equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change. Heat capacity is an extensive property of matter, meaning that it is proportional to the size of the system.

You might be interested in

Heat naturally flows from an object that has a _______________ temperature to an object that has a _______________ temperature.

GaryK [48]

Answer:

higher, lower, external work, 100 %, work.

Explanation:

These paragraphs refer to the second law of thermodynamics. There are two statements for the second law of thermodynamics. They are as follows:

KELVIN STATEMENT:

All the heat from a source can never be transferred to the sink without the rejection of some heat.

CLAUSIUS STATEMENT:

Heat can not be transferred from a colder body to a hotter body without the application of som external work.

According to the statements the blanks can be filled as follows:

Heat naturally flows from an object that has a higher temperature to an object that has a Lower temperature. Heat can be made to flow in the reverse direction if external work is done. A machine can never have an efficiency of 100 %. This means that heat energy can never be fully converted into work energy.

7 0

3 years ago

Read 2 more answers

The waves with the lowest energy and lowest frequencies of the electromagnetic spectrum are the

Andru [333]

The waves with the lowest energy and lowest frequencies of the electromagnetic spectrum are the "Radio waves"

So, option B is your answer

Hope this helps!

5 0

4 years ago

As an intern at an engineering firm, you are asked to measure the moment of inertia of a large wheel for rotation about an axis

klio [65]

Hi there!

We can begin by finding the acceleration of the block.

Use the kinematic equation:

$d = v_0t + \frac{1}{2}at^2$

The block starts from rest, so:

$d = \frac{1}{2}at^2\\\\12 = \frac{1}{2}a(4^2)\\\\\frac{24}{16} = a = 1.5 m/s^2$

Now, we can do a summation of forces of the block using Newton's Second Law:

$F = ma = m_bg - T$

mb = mass of the block

T = tension of string

Solve for tension:

$T = m_bg - ma = 8.2(9.8) - 8.2(1.5) = 68.06 N$

Now, we can do a summation of torques for the wheel:

$\Sigma \tau = rF\\\\\Sigma\tau = rT$

Rewrite:

$I\alpha = rT$

We solved that the linear acceleration is 1.5 m/s², so we can solve for the angular acceleration using the following:

$\alpha = a/r\\\\\alpha = 1.5/.42= 3.57 rad/sec^2$

Now, plug in the values into the equation:

$I(3.57) = (0.42)(68.06)\\\\I = (0.42)(68.06)/(3.57) = \boxed{8.00 kgm^2}$

8 0

3 years ago

A 20.0 F capacitor initially charged to 30.0 uC is discharged through a 3.00 k resistor. How long does it take to reduce the cap

Maslowich

Answer:

t = 0.04159 s

Explanation:

when a capacitor and resister are connected in series. charge on its plates decreases exponentially

$q = qo * e^{\frac{-t}{RC}}$

where,

CHARGE q =15.0 C

INITIAL CHARGE q_0 = 30.0 uc

Resistor R = 20.0 F

capacitor C = 3.00

$15 = 30* e^{\frac{- t}{(20* 10^{-6} * 3* 1000)}$

t = 0.04159 s

3 0

4 years ago

Dave rows a boat across a river at 4.0 m/s. the river flows at 6.0 m/s and is 360 m across.

Ad libitum [116K]

a) Let's call x the direction parallel to the river and y the direction perpendicular to the river.

Dave's velocity of 4.0 m/s corresponds to the velocity along y (across the river), while 6.0 m/s corresponds to the velocity of the boat along x. Therefore, the drection of Dave's boat is given by:

$\theta= arctan(\frac{v_y}{v_x})=arctan(\frac{4.0 m/s}{6.0 m/s})=arctan(0.67)=33.7^{\circ}$

relative to the direction of the river.

b) The distance Dave has to travel it S=360 m, along the y direction. Since the velocity along y is constant (4.0 m/s), this is a uniform motion, so the time taken to cross the river is given by

$t=\frac{S_y}{v_y}=\frac{360 m}{4.0 m/s}=90 s$

c) The boat takes 90 s in total to cross the river. The displacement along the y-direction, during this time, is 360 m. The displacement along the x-direction is

$S_x = v_x t =(6.0 m/s)(90 s)=540 m$

so, Dave's landing point is 540 m downstream.

d) If there were no current, Dave would still take 90 seconds to cross the river, because its velocity on the y-axis (4.0 m/s) does not change, so the problem would be solved exactly as done at point b).

7 0

4 years ago