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
olchik [2.2K]
3 years ago
11

approximately what force,FM must the extensor muscle in the upper arm exert on the lower arm to hold a 7.6kg shot put? assume th

e lower arm has a mass of 2.8kg and it's CG is 11.6cm froom the pivot point.
Physics
1 answer:
MAXImum [283]3 years ago
7 0
Lets do the sum of the forces about the elbow joint.

Fm = Force of Muscle; Fe = Force Elbow; Fb = Force Ball

Sum Force about Joint = (-2.5)Fm + 12.5Fe + 30Fb = 0

(-2.5)Fm + 12.5(2.8) + 30(6.9) = 0

Fm = 96.8kg

Fm = 96.8 * 9.8 = 948.6N

Do you understand why the -2.5 is negative?
<span> Because I put the origin at the joint. So when you go left it is negative and when you go right it is positive. </span>
You might be interested in
A child with mass of 25 kg gets into a toy car with mass of 80 kg on a playground, causing it to sink on its springs (with effec
Bess [88]

Answer:

The frequency of the oscillation is 0.9Hz

Explanation:

This problem bothers on simple harmonic motion of a spring

Given data

Mass of the child m= 25kg

Spring constant k=791 N/m

Amplitude a= 31cm

But the period of the motion as a result of the adults sholve is expressed as

T=2π√m/k

T=2*3.142√25/791

T=6.284√0.031

T=6.284*0.176

T=1.11 sec

But frequency F=1/T

F=1/1.11

F=0.9Hz

4 0
3 years ago
Why is it important to develop alternative energy sources
Aliun [14]

Answer:

The alternative energy sources are defined as those resources that are used in place of the natural and non-renewable resources. This resources plays an important role in the conservation of natural resources.

The fossil fuels are the resources on which the people are directly dependent. Burning up of these fossils leads to the emission of carbon, which has a direct impact on earth. A small increase in the amount of carbon dioxide can lead to the increase in the surface temperature of earth.

In addition to this, these fossil fuels such as coal, petroleum, oil and natural gases are found to be present in a limited proportion, and it is a very expensive process to obtain these resources, so sustainable development method must be adopted in order to save this natural resources for the future generation.

Some of the examples of alternative resources that are widely used in place of fossil fuels are wind energy, solar energy, tidal energy, biomass energy and bio-fuels.

Thus, it is very important to develop and use alternative resources.

7 0
3 years ago
a new planet is discovered that has twice the earth’s mass and twice the earth’s radius. on the surface of this new planet, a pe
Irina18 [472]

Answer: 250n

Explanation:

The formula for gravitational force is: F = (gMm)/r^2

There are two factors at play here:

1) The mass of the planet 'M'

2) The radius 'r'

We can ignore the small M and the g, they are constants that do not alter the outcome of this question.

You can see that both M and r are double that of earth. So lets say earth has M=1 and r=1. Then, new planet would have M=2 and r=2. Let's sub these two sets into the equation:

Earth. F =  M/r^2 = 1/1

New planet. F = M/r^2 = 2/4 = 1/2

So you can see that the force on the new planet is half of that felt on Earth.

The question tells us that the force on earth is 500n for this person, so then on the new planet it would be half! So, 250n!

8 0
2 years ago
HELP QUICK!!!WILL GIVE BRAINLIEST!! According to the Sternberg's triarchic theory of intelligence, information synthesis is a st
maxonik [38]
Formulated in the 1980s by Robert Sternberg<span>, the </span>triarchic theory<span> distinguishes three aspects of </span>intelligence<span>: analytic skills, such as the ability to think abstractly and evaluate </span>information<span>; creativity, the ability to invent novel solutions or ideas; and practical skills, which enable one to cope with concrete ...</span>
4 0
3 years ago
Read 2 more answers
In doing a load of clothes, a clothes dryer uses 16 A of current at 240 V for 45 min. A personal computer, in contrast, uses 2.7
jasenka [17]

Explanation:

Given that,

Current of clothes dryer, I = 16 A

Voltage, V = 240 V

Time, t = 45 min = 2700 s

Current of personal computer, I' = 2.7 A

Voltage, V' = 120 C

Energy used by clothes dryer is given by :

E=I^2Rt\\\\E=IVt\\\\E=16\times 240\times 2700\\E=1.03\times 10^7\ J

Let t' is the time for this computer to "surf" the internet. Again using formula of energy used as :

E=I'V't'\\\\t'=\dfrac{E}{I'V'}\\\\t'=\dfrac{1.03\times 10^7}{2.7\times 120}\\\\t'=31790.12\ s\\\\t'=8.83\ h

So, for 8.83 hours you could use this computer to "surf" the internet.

6 0
3 years ago
Other questions:
  • The spring of a spring gun has force constant k = 400 N/m and negligible mass. The spring is compressed 6.00 cm and a ball with
    11·1 answer
  • Tina and her puppy are tugging on a rope, each pulling on opposite ends.
    13·2 answers
  • What are two real life examples that resemble peristalsis?
    9·1 answer
  • A steam flows from high elevation to low elevation very quickly, has steep canyon walls, and rapidly moving water. What type of
    14·1 answer
  • A message is sent from the Galileo spacecraft orbiting Jupiter to earth at a distance of 928,000,000km. If it took the signal 51
    5·2 answers
  • A piece of putty and a tennis ball with the same mass are thrown against a wall with the same velocity. Which object experiences
    5·1 answer
  • What is most likely to result immediately after a rainforest in Brazil is clear-cut?secondary succession
    15·2 answers
  • which of the following statements is a reasonable conclusion about the Arctic ecosystem? a)The number of offspring produced is a
    7·1 answer
  • 1. Do you feel Doc's habits and routine have led to his success? Explain
    11·1 answer
  • What science projects should I do? Please just choose something basic!
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!