PHYSICS MIDDLE SCHOOL

The latent heat of fusion of alcohol is 50 kcal/kg and its melting point is -54oC. It has a specific heat of 0.60 in its liquid state. Calculate the energy needed to melt 2.0 kg of solid alcohol at -54o and raise it to a temperature of -4°C.40. kcal
100 kcal
160 kcal
280 kcal

Answers

Answer 1

Answer:

Answer:

Explanation:

To melt the alcohol

Heat needed = M . L = 2 . 25 = 50 kcal

To warm up the alcohol

Heat needed = M . sp. ht. . ∆t = 2 . 0.6 . 100 = 120 kcal

Total heat needed = 170 kcal

Assuming that 0.6 kcal/ kg / ˚C is the specific heat and that the answer is wanted in kcal ( a rather odd unit to be in use here.)

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A car traveling with constant speed travels 150 km in 7200 s. What is the speed of the car?Express the speed to two significant figures and include the appropriate units.

Answers

The speed of the car is 75 km/h

Further explanation

These are the formulas that we have to remember before solving the problem.

Speed is the rate of change of distance.

$\large { \boxed {v = (d)/(t)}}$

v = speed ( m/s )

d = distance ( m )

t = time ( s )

Acceleration is the rate of change of velocity.

$\large { \boxed {a = (\Delta v)/(t)}}$

a = acceleration ( m/s² )

Δv = change in speed ( m/s )

t = time ( s )

Let us now tackle the problem!

Given:

distance = d = 150 km

time taken = t = 7200 s = 2 hours

Unknown:

velocity = v = ?

Solution:

$v = (d)/(t)$

$v = (150)/(2)$

$\large {\boxed {v = 75~km/h} }$

The acceleration of the car is 0 m/s² because it travels with constant speed.

We could also plot the distance vs time graph as shown in the attachment.

Learn more

Velocity of A Runner : brainly.com/question/3813437
Kinetic Energy : brainly.com/question/692781
Acceleration : brainly.com/question/2283922

Answer details

Grade: Middle School

Subject: Physics

Chapter: Kinematics

Keywords: indycar top speed of a fastest police car has ever gone

Final answer:

The car's speed is 75 km/hour, as determined by dividing the total distance travelled (150 km) by the total time taken (2 hours).

Explanation:

To answer this question, we use the

formula for speed

, which is distance traveled divided by the time taken. Here, the distance travelled by the car is 150 km and the time taken is 7200 s (which is equal to 2 hours). Therefore, the speed will be 150 km divided by 2 hours, resulting in a speed of

75 km/hour

, stated to the correct number of significant figures.

Learn more about Speed Calculation here:

brainly.com/question/35969362

#SPJ6

Which of the following lists the Earth’s layers in order from hottest to coldest in temperature?A.outer core, mantle, inner core, crust
B.crust, mantle, outer core, inner core
C.inner core, outer core, mantle, crust
D.mantle, crust, inner core, outer core

Answers

The answer is C, Inner core, outer core, mantle, crust.

Well,

Logically, the deeper we go, the hotter it will get.

It turns out that the innermost part of the lithosphere is the hottest, while the outermost part of the lithosphere is the hottest (suprise!).

Option C is correct.

Several objects were dropped from a balcony. Using the data below, determine which statements must be true regarding the rate of force of each falling object. Neglect (ignore) air resistance.Object

Mass

Diameter

Height of drop

Tennis Ball

0.06 kg

6.6 cm

5 m

Baseball

0.15 kg

74 cm

5 m

Bowling Ball

5 kg

21 cm

5 m

Golf Ball

0.04 kg

4.3 cm

5 m

Statement 1: All balls hit the ground at the same time

Statement 2: All balls hit the ground with different forces

Statement 3: The bowling ball hit the ground first and the tennis and golf ball hit the ground last

Statement 4: It is not possible to tell how much force each ball hit the ground with

Answers

Answer:

statement 2

Explanation:

All hit at the same time

What can you conclude about why Arrhenius bases are considered a limited case of Bronsted-Lowry bases.All Arrhenius bases can act as proton acceptors
Arrhenius bases release hydronium ions in solution.
Arrhenius bases act as proton and hydroxide acceptors.
Arrhenius bases produce only hydroxide ions in solution

Answers

Answer: C
Hope this help!!!

Answer:

the 3rd one

Explanation:

Select the best terms from the drop-down menus that fit the nuclear medicine descriptions.gamma-ray detection from tracers
assess disease progression, tissue function
a hybrid scan that involves nuclear medicine and X-ray imaging
radiation treatment near or within the tumor from implanted "seeds"

Answers

Answer:

Hi there, so gamma-ray detection from tracers: Pet Scan, assess disease progression, tissue function: Nuclear Medicine Scan, a hybrid scan that involves nuclear medicine and x-ray imaging: PET/CT, and lastly radiation treatment near or within the tumor from implanted "seeds": Brachytherapy. Hope this helps <3.

Explanation:

btw you cute <3.

Answer:

Pet Scan

Nuclear Medicine

PET/CT

Brachytherapy

Copper has a specific heat of 0.385 j. A piece of copper absorbs 5000 J of energy and undergoes a temperature change from 100 Celsius to 200 degrees Celsius. What is the mass of the piece of copper?

Answers

The mass of the piece of copper will be 130 kg. In the International System of Units (SI), the kilogram is the unit of mass.

What is mass?

Mass is a numerical measure of inertia, which is a basic feature of all matter. It is, in effect, a body of matter's resistance to a change in speed or position caused by the application of a force.

The energy absorbed as;

$\rm \triangle E = mC \triangle t \n\n m = (\triangle E )/(mC) \n\n m = (5000 )/(0.385 (200-100)) \n\n m=130 \ kg$