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
grandymaker [24]
3 years ago
11

What is the force exerted by a solid surface that opposes gravity?

Physics
2 answers:
jonny [76]3 years ago
6 0

Electromagnetic force between the molecules! 
Ann [662]3 years ago
6 0
The force exerted upward that opposes gravity is the Normal Force.
You might be interested in
Photoelectric effect:
Lynna [10]

Answer:

A. K = 0.546 eV

B. cooper and iron will not emit electrons

Explanation:

A. This is a problem about photoelectric effect. Then you have the following equation:

K=h\nu-\Phi=h\frac{c}{\lambda} -\Phi   (1)

K: kinetic energy of the ejected electron

Ф: Work function of the metal = 2.48eV

h: Planck constant = 4.136*10^{-15} eV.s

λ: wavelength of light = 410nm - 750nm

c: speed of light = 3*10^8 m/s

As you can see in the equation (1), higher the wavelength, lower the kinetic energy. Then, the maximum kinetic energy is obtained with the lower wavelength (410nm). Thus, you replace the values of all variables :

K=(4.136*10^{-15}eV)\frac{3*10^8m/s}{410*10^{-9}m}-2.48eV\\\\K=0.546eV

B. First you calculate the energy of the photon with wavelengths of 410nm and 750nm

E_1=(4.136*10^{-15}eV)\frac{3*10^{8}m/s}{410*10^{-9}m}=3.02eV\\\\E_2=(4.13610^{-15}eV)\frac{3*10^{8}m/s}{750*10^{-9}m}=1.6544eV

You compare the energies E1 and E2 with the work functions of the metals and you can conclude:

sodium = 2.3eV < E1

cesium = 2.1 eV < E1

cooper = 4.7eV > E1 (this metal will not emit electrons)

iron = 4.5eV > E1 (this metal will not emit electrons)

5 0
3 years ago
Which of the following materials is a good conductor of electric current??? Anyone the options are A.) a rubber tire B.) a silve
bekas [8.4K]
A silver spoon (B.) A silver spoon is metal so it would be the best answer out of the four. a rubber tire is a good insulator but not a good conductor. Thank you!
6 0
2 years ago
The density of water is:
mario62 [17]
It is 1,000kg/m³ i hope this helps you with something
4 0
3 years ago
Studies have shown that driving after drug use was more common among drivers who were
Vesnalui [34]
Killed in accident or injured
5 0
3 years ago
A boy wants use his slingshot to shoot a water balloon into the air. His
Marrrta [24]

Answer:

A. 70 m OS the correct one

5 0
3 years ago
Other questions:
  • Yolanda has decided she is going to be a nurse. What is the next step she should take to make her career goals a reality? a. Cre
    5·3 answers
  • A slice of bread contains about 100 kcal. If specific heat of a person were 1.00 kcal/kg·°C, by how many °C would the temperatur
    6·1 answer
  • A beetle crawls from x=1.09m to x=2.55m in 12.8s. what was the average velocity?
    12·1 answer
  • The velocity of in water is 1500 m/s.
    5·1 answer
  • Heat is best defined as
    15·1 answer
  • How do distinctive rock strata support the theory of continental drift?
    9·1 answer
  • An object
    11·1 answer
  • The force experienced by an electron in a field between parallel plates is proportional to which of the following? Select all th
    11·1 answer
  • A scientist uses a camera to study the stars.
    7·2 answers
  • Sage measured her rectangular house as 15.24 m long and 9.1 m wide. Using her calculator, she multiplied the length by the width
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!