Im not going to lie, this is a physics Q right here<br> plz guys im being serious i need help

Why do you think festival dances should be introduced to the younger generations of today

Nimfa-mama [501]

Answer:

Festival dances should be introduced to the younger generations of today because they teach them about different cultures. Festival dances are also a way to be active and have a fun time.

Explanation:

4 0

3 years ago

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g The steam above a freshly made cup of instant coffee is really water vapor droplets condensing after evaporating from the hot

geniusboy [140]

Answer:

the final temperature = 74.33°C

Explanation:

Using the expression Q = mcΔT for the heat transfer and the change in temperature .

Here ;

Q = heat transfer

m = mass of substance

c = specific heat

ΔT = the change in temperature

The heat Q required to change the phase of a sample mass m is:

Q = m $L_v$

where;

$L_v$ is the latent heat of vaporization.

From the question ;

Let M represent the mass of the coffee that remains after evaporation is:

ΔT = $\frac{mL_v}{MC}$

where;

m = 2.50 g

M = (240 - 2.50) g = 237.5 g

$L_v$ = 539 kcal/kg

c = 1.00kcal/kg. °C

ΔT = $\frac{2.50*539 \ kcal /kg}{237.5 g *1.00 \ kcal/kg . ^0C}$

ΔT = 5.67°C

The final temperature of the coffee is:

$T_f = T_i -$ ΔT

where ;

$T_I$ = initial temperature = 80 °C

$T_f$ = (80 - 5.67)°C

$T_f$ = 74.33°C

Thus; the final temperature = 74.33°C

8 0

3 years ago

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Scientists studying an anomalous magnetic field find that it is inducing a circular electric field in a plane perpendicular to t

yarga [219]

Answer

The rate at which the magnetic field is changing is $[\frac{dB}{dt} ] = 0.000467 T/s$

Explanation

From the question we are told that

The electric field strength is $E = 3.5mV/m = 3.5 *10^{-3} \ V/m$

The radius is $r = 1.5 \ m$

The rate of change of the magnetic field is mathematically represented as

$\frac{d \phi }{dt} = \int\limits^{} {E \cdot dl}$

Where $dl$ is change of a unit length

$\frac{d \phi}{dt} = A * \frac{dB}{dt}$

Where A is the area which is mathematically represented as

$A = \pi r^2$

So

$E \int\limits^{} { dl} = ( \pi r^2) (\frac{dB}{dt} )$

$E L = ( \pi r^2) (\frac{dB}{dt} )$

where L is the circumference of the circle which is mathematically represented as

$L = 2 \pi r$

So

$E (2 \pi r ) = (\pi r^2 ) [\frac{dB}{dt} ]$

$E = \frac{r}{2} [\frac{dB}{dt} ]$

$[\frac{dB}{dt} ] = \frac{E}{ \frac{r}{2} }$

substituting values

$[\frac{dB}{dt} ] = \frac{3.5 *10^{-3}}{ \frac{15}{2} }$

$[\frac{dB}{dt} ] = 0.000467 T/s$

8 0

3 years ago

A brass alloy is known to have a yield strength of 240 MPa (35,000 psi), a tensile strength of 310 MPa (45,000 psi), and an elas

Karo-lina-s [1.5K]

Answer:

Here Strain due to testing is greater than the strain due to yielding that is why computation of load is not possible.

Explanation:

Given that

Yield strength ,Sy= 240 MPa

Tensile strength = 310 MPa

Elastic modulus ,E= 110 GPa

L=380 mm

ΔL = 1.9 mm

Lets find strain:

Case 1 :

Strain due to elongation (testing)

ε = ΔL/L

ε = 1.9/380

ε = 0.005

Case 2 :

Strain due to yielding

$\varepsilon' =\dfrac{S_y}{E}$

$\varepsilon' =\dfrac{240}{110\times 1000}$

ε '=0.0021

Here Strain due to testing is greater than the strain due to yielding that is why computation of load is not possible.

For computation of load strain due to testing should be less than the strain due to yielding.

4 0

3 years ago

You will be colliding two carts in this lab. Select all the systems for which you predict the total momentum of the system will

baherus [9]

From the momentum conservation we know that the initial momentum is equal to the final momentum. The momentum in a singular way can be defined as the product between the mass and the velocity of an object. In the presented system, however, there are two objects, therefore the mass of both and the speed of both, before and after the collision must be taken into account. Mathematically we could describe this as

$m_1u_1+m_2u_2 = m_1v_1+m_2v_2$

Here,

$m_{1,2}$ = Mass of each object

$u_{1,2}$ = Initial velocity of each object

$v_{1,2}$ = Final velocity of each object

From here we can realize that it is necessary to use the system on both cars to be able to predict what will happen either with their masses, or their speeds.

The correct answer is C.

6 0

3 years ago

Im not going to lie, this is a physics Q right here plz guys im being serious i need help