1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Lerok [7]
3 years ago
12

Mr. Hoffman, a science teacher, drove 10 miles to school from home in 20 minutes. He drove the 10 miles home in 30 min. His aver

age velocity was _____ m/s.
Physics
2 answers:
olga2289 [7]3 years ago
7 0
His average velocity for the day was 0. He ended where he started so his displacement was 0.
Andrews [41]3 years ago
4 0

zero.

Because he finished right where he started. his total displacement zero. therefore, his average velocity was also zero  

You might be interested in
A person notices a mild shock if the current along a path through the thumb and index finger exceeds 82 µA. Find the maximum all
Drupady [299]

Answer:

V_{voltage}=19.68V

Explanation:

Given data

Current I=82µA=82×10⁻⁶A

Resistance R=2.4×10⁵Ω

to find

Voltage

Solution

From Ohms law we know that:

V_{voltage}=I_{current}*R_{resistance}\\V_{voltage}=82*10^{-6}*2.4*10^{5}   \\V_{voltage}=19.68V

4 0
3 years ago
A 900 kg car is traveling at 20 m/s along the road. What force must be applied to the car to stop it in a distance of 30 m2 Assu
serg [7]

Answer:

A. 6000 N

Explanation:

v²=u²+2as

0²=20²+2x30xa

-400=60a

a=-400/60

a =-6.667m/s²

f =ma

f = 900 x 6.667 = 6003N

F = 6000N

5 0
3 years ago
Initilal velocity of projectile at an angle of 22.5° is 10m/s. Then what is the magnitude of range of projectile?
crimeas [40]

Answer:

0.707m

Explanation:

from formula of range i.e R=Usin2Q/g

3 0
3 years ago
A gas at 5.00 atm pressure was stored in a tank during the winter at 5.0 °C. During the summer, the temperature in the storage a
saw5 [17]

Answer:

a) 5.63 atm

Explanation:

We can use combined gas law

<em>The combined gas law</em> combines the three gas laws:

  • Boyle's Law,   (P₁V₁ =P₂V₂)
  • Charles' Law  (V₁/T₁ =V₂/T₂)
  • Gay-Lussac's Law.  (P₁/T₁ =P₂/T₂)

It states that the ratio of the product of pressure and volume and the absolute temperature of a gas is equal to a constant.

P₁V₁/T₁ =P₂V₂/T₂

where P = Pressure, T = Absolute temperature, V = Volume occupied

The volume of the system remains constant,

So, P₁/T₁ =P₂/T₂

a) \frac{5}{278} =\frac{P_2}{313}  \\\\P_2=\frac{5*313}{278}\\ P_2 = 5.63 atm

7 0
3 years ago
A 5.00-A current runs through a 12-gauge copper wire (diameter 2.05 mm) and through a light bulb. Copper has 8.5 * 1028 free ele
evablogger [386]

Answer:

a)n= 3.125 x 10^{19 electrons.

b)J= 1.515 x 10^{6 A/m²

c)V_{d =1.114 x 10^{4m/s

d) see explanation

Explanation:

Current 'I' = 5A =>5C/s

diameter 'd'= 2.05 x 10^{-3 m

radius 'r' = d/2 => 1.025 x 10^{-3 m

no. of electrons 'n'= 8.5 x 10^{28}

a) the amount of electrons pass through the light bulb each second can be determined by:

I= Q/t

Q= I x t => 5 x 1

Q= 5C

As we know that: Q= ne

where e is the charge of electron i.e 1.6 x 10^{-19C

n= Q/e => 5/ 1.6 x 10^{-19

n= 3.125 x 10^{19 electrons.

b)  the current density 'J' in the wire is given by

J= I/A => I/πr²

J= 5 / (3.14 x (1.025x 10^{-3)²)

J= 1.515 x 10^{6 A/m²

c) The typical speed'V_{d' of an electron is given by:

V_{d = \frac{J}{n|q|}

    =1.515 x 10^{6 / 8.5 x 10^{28} x |-1.6 x 10^{-19|

V_{d =1.114 x 10^{4m/s

d) According to these equations,

J= I/A

V_{d = \frac{J}{n|q|} =\frac{I}{nA|q|}

If you were to use wire of twice the diameter, the current density and drift speed will change

Increase in the diameter increase the cross sectional area and decreases the current density as it has inverse relation.

Also drift velocity will decrease as it is inversely proportional to the area

 

5 0
3 years ago
Read 2 more answers
Other questions:
  • Salt is dissolved in a flask of tap water. Distilling the mixture causes the salt to separate from the water. Which type of ener
    5·2 answers
  • Sunlight has its maximum intensity at a wavelength of 4.83 x 10'm; wha energy does this correspond to in e?
    7·1 answer
  • A swimmer can swim at a velocity v in still water. She swims upstream a distance d against the current, which has a velocity u.
    10·1 answer
  • The atomic number of yttrium is 39. The atomic mass of one of its isotopes is 89. How many neutrons are in an atom of this isoto
    10·1 answer
  • Does the length of a persons hair affect the power of static electricity
    15·2 answers
  • PLEASE HELP ASAPPPP!!!!!
    6·1 answer
  • Pls someone help me
    7·1 answer
  • Can you answer this math homework? Please!
    12·1 answer
  • Which type of energy moves from one object to another by touching?
    6·2 answers
  • In a hard disk drive, a constant torque of 14 N⋅m is applied to the magnetic disk when the drive starts recording data. The magn
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!