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
Papessa [141]
3 years ago
8

After the first few seconds of a race, a runner runs at the same speed until she approaches the finish line, at which point she

increases her speed. Which statement best explains why she only did work at the beginning and end of the race? (Ignore work done against air resistance and friction.)
Physics
1 answer:
Rzqust [24]3 years ago
5 0

DUJFIOflmC VANWSER

EXPLANTATION

You might be interested in
A) An automobile light has a 1.0-A current when it is connected to a 12-V battery. Determine the resistance of the light.
kirill [66]

Answer:

The resistance in first case is 12 Ω, power delivered is 12 W, and potential difference is 0.01 V

Explanation:

Given:

(A)

Current I = 1 A

Voltage V = 12 V

For finding the resistance,

  V = IR

  R = \frac{V}{I}

  R = \frac{12}{1}

  R = 12Ω

(B)

For finding power delivered,

  P = I^{2} R

  P = (1) ^{2} \times 12

  P = 12 Watt

(C)

For finding the potential difference,

   V = IR

   V = 5 \times 10^{-3} \times 2

   V = 10 \times 10^{-3}

   V = 0.01 V

Therefore, the resistance in first case is 12 Ω, power delivered is 12 W, and potential difference is 0.01 V

4 0
3 years ago
Jake calculates that the frequency of a wave is 500 hertz and that the wave is moving at 1,250 m/s. What is the wavelength of th
Neko [114]
Frequency (f) = 500 hz (SI)
Velocity (V) = 1250 m/s (SI)
Wavelength (Lambda) = ? meters

v =  \lambda \times f
1250 =  \lambda \times 500 \\ \lambda = 1250 \div 500 \\ \lambda = 2.5 \: meters
6 0
3 years ago
No force is necessary to
igor_vitrenko [27]
No force is necessary to keep a moving object moving (in a straight line at a constant speed).
4 0
3 years ago
To initiate a nuclear reaction, an experimental nuclear physicist wants to shoot a proton into a 5.50-fm-diameter 12C nucleus. T
vladimir1956 [14]

Answer:

Explanation:

kinetic energy required = 1.80 MeV

= 1.8 x 10⁶ x 1.6 x 10⁻¹⁹ J

= 2.88 x 10⁻¹³ J

If v be the velocity of proton

1/2 x mass of proton x v² = 2.88 x 10⁻¹³

= .5 x 1.67 x 10⁻²⁷ x v² = 2.88 x 10⁻¹³

v² = 3.45 x 10¹⁴

v = 1.86 x 10⁷ m /s

If V be the potential difference required

V x e = kinetic energy . where e is charge on proton .

V x 1.6 x 10⁻¹⁹ = 2.88 x 10⁻¹³

V = 1.8 x 10⁶ volt .

3 0
3 years ago
During a circus act, an elderly performer thrills the crowd by catching a cannon ball shot at him. The cannon ball has a mass of
Ipatiy [6.2K]

Answer:

m v1 = (m + M) v2

v2 = m v1 / (m + M)

v2 = 7 * 74 / (74 + 65)

3.73 m/s

74 kg is too heavy for the cannonball (over 150 lbs)

4 0
3 years ago
Other questions:
  • On a safari, a team of naturalists sets out toward a research station located 4.63 km away in a direction 38.7 ° north of east.
    13·2 answers
  • The measured mass of a body is found to be 110g. The length is measured by a meter scale. Actual mass and length of the body are
    5·1 answer
  • Complete the sentence
    13·1 answer
  • The vacuum tube was replaced with what electrical component?
    15·1 answer
  • Indicate whether the statement is true or false. an astronaut weighs the same on earth as in space.
    11·2 answers
  • 40 POINTS!!! + BRAINLIEST!!!
    11·1 answer
  • What is the wavelength associated with an electron with a velocity of 4.8X10s m/s? (Mass of the electron is 9.1X10-31kg)?
    9·1 answer
  • Water is kept in a vessel at a temperature of 100°C. What would happen if a metal ball having a temperature of 30°C is dropped i
    7·1 answer
  • Please show work with the answer and thank you
    14·1 answer
  • 5. Your friend claims that the Moon’s repeated orbit around Earth causes the cycle of the Moon’s phases.
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!