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
adell [148]
2 years ago
8

We cab calculate work because we know the force and distance.what else would we need to know to calculate power

Physics
1 answer:
san4es73 [151]2 years ago
6 0

We would need to know how long it took to do the work.

Power = (work) / (time).

You might be interested in
Terry can ride 30 miles in 2 hours. If his riding speed is
Anni [7]

Answer:  20.4 miles

Explanation:

Here we need to use the equation:

Velocity = Distance/Time.

Initially we have that he can travel 30 miles in 2 hours, so the velocity is:

V = 30mi/2h = 15mph

Now, we reduce the velocity by 3 mph, so the new velocity is 15mph - 3 mph = 12mph.

Now we want to know the distance traveled in 1.7 hours with this velocity, this is.

Velocity*Time = Distance

12mi/h*1.7h = 20.4 miles

7 0
2 years ago
What is the magnitude of the torque about his shoulder if he holds his arm straight out to his side, parallel to the floor
const2013 [10]

Complete Question

An athlete at the gym holds a 3.0 kg steel ball in his hand. His arm is 70 cm long and has a mass of 4.0 kg. Assume, a bit unrealistically, that the athlete's arm is uniform.

What is the magnitude of the torque about his shoulder if he holds his arm straight out to his side, parallel to the floor? Include the torque due to the steel ball, as well as the torque due to the arm's weight.

Answer:

The torque is  \tau = 34.3 \  N\cdot m

Explanation:

From the question we are told that

   The mass of the steel ball is  m  =  3.0 \  kg

    The length of arm is  l =  70 \ cm  = 0.7 \  m

    The mass of the arm is m_a  = 4.0 \  kg

Given that the arm of the athlete is uniform them the distance from the shoulder to the center of gravity of the arm is mathematically represented as

       r = \frac{l}{2}

=>    r = \frac{ 0.7}{2}  

=>    r = 0.35 \ m  

Generally the magnitude of torque about the athlete shoulder is mathematically represented as

      \tau =  m_a * g * r  + m * g *  L

=>    \tau =  4 * 9.8 * 0.35 + 3 * 9.8 *  0.70

=>    \tau = 34.3 \  N\cdot m

5 0
2 years ago
Preston tossed a red ball upward and it reaches a maximum height of 3.0. What is the final velocity when it returns to prestons
Leokris [45]
That will depend on the units of the 3.0. We need to know if it's 3 feet, 3 yards, 3 meters, or 3 miles. Each one will have a different answer.
5 0
2 years ago
A 4.30 g bullet moving at 943 m/s strikes a 730 g wooden block at rest on a frictionless surface. The bullet emerges, traveling
Ymorist [56]

Answer:

(a)2.7 m/s

(b) 5.52 m/s

Explanation:

The total of the system would be conserved as no external force is acting on it.

Initial momentum = final momentum

⇒(4.30 g × 943 m/s) + (730 g × 0) = (4.30 g × 484 m/s) + (730 g × v)

⇒ 730 ×v = (4054.9 - 2081.2) =1973.7

⇒v=2.7 m/s

Thus, the resulting speed of the block is 2.7 m/s.

(b) since, the momentum is conserved, the speed of the bullet-block center of mass would be constant.

V_{COM} = \frac{m_b}{m_b+m_{bl}}v_{bi}=\frac{4.30}{4.30+730}\times 943 m/s = 5.52 m/s

Thus, the speed of the bullet-block center of mass is 5.52 m/s.

4 0
3 years ago
3 PHYSICAL SCIENCE: In order to figure out what is in a sealed box, you perform some tests. The box seems heavy for its size and
rjkz [21]
Some sort of magnetic metal

Metals are heavier per cubic unit than other materials such as air or water, and also are much more magnetic than other materials
7 0
3 years ago
Other questions:
  • The light bulb transfers electrical energy into light. What is one type of energy that is also generated that is NOT a desired e
    11·2 answers
  • There is a large box and a small box on a table. The same force is applied to both boxes. The large box moves two feet and the s
    8·2 answers
  • a beaker has mass of 125 g. what is the mass of liquid if the beaker plus liquid have a mass of 232 g?
    5·1 answer
  • Find the potential energy associated with a 79-kg hiker atop New Hampshire's Mount Washington, 1900 m above sea level. Take the
    11·1 answer
  • A mass–spring system moves with simple harmonic motion along the x axis between turning points at x = 10x=10 cm and x_2 = 30x ​2
    13·1 answer
  • What is charging by conduction. <br> Can you also give an real life example of it.
    8·2 answers
  • ANSWER ASAP PLEASE 15 POINTS
    8·1 answer
  • What is a mixture?
    13·2 answers
  • SOMEBODY ONCE TOLD ME THE WORLD WAS GONNA ROLL ME
    6·1 answer
  • Please help thank you!
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!