What is the net force on the box? Be sure to specify direction.<br> 15 N<br> 10 N

A 51-kg woman runs up a vertical flight of stairs in 5.0 s. Her net upward displacement is 5.0 m. Approximately, what average po

Vika [28.1K]

Answer:

The average power the woman exerts is 0.5 kW

Explanation:

We note that power, P = The rate at which work is done = Work/Time

Work = Energy

The total work done is the potential energy gained which is the energy due to vertical displacement

Given that the vertical displacement = 5.0 m, we have

Total work done = Potential energy gained = Mass, m × Acceleration due to gravity, g × Vertical height, h

m = 51 kg

g = Constant = 9.81 m/s²

h = 5.0 m

Also, time, t = 5.0 s

Total work done = 51 kg × 9.81 m/s²× 5 m = 2501.55 kg·m²/s² = 2501.55 J

P = 2501.55 J/(5 s) = 500.31 J/s = 500.31 W ≈ 500 W = 0.5 kW.

6 0

3 years ago

A car of mass 600 Kg is moving at 15m/s. Calculate its momentum.

mr_godi [17]

Mass=600kg
Velocity =15m/s
Momentum(p)=?
Now,
P=mass x velocity
=600x15
=9000kgm/s

3 0

3 years ago

a 2500 kg car going 35 m/a hits a 4000kg truck that is sitting still. What is the velocity of the truck if the car transfers all

lianna [129]

Answer:

Velocity of truck is 21.875 m/s.

Explanation:

Given:

Mass of the car (m) = 2500 kg

Initial speed of the car (u) = 35 m/s

Mass of the truck (M) = 4000 kg

Initial speed of the truck (U) = 0 m/s (Rest)

As per question, the total momentum of the car gets transferred to the truck.

Therefore, the final momentum of the car is 0.

Momentum is given as the product of mass and velocity.

So, if momentum becomes zero means the velocity becomes 0.

Therefore, final velocity of the car (v) = 0 m/s

Let the final velocity of truck be 'V' m/s.

Now, during collision, the total momentum remains conserved.

Initial momentum = Final momentum.

Initial momentum of car + Initial momentum of truck = Final momentum of car + Final momentum of truck.

⇒ $mu+MU=mv+MV\\\\2500\times 35+4000\times 0=2500\times 0+4000\times V\\\\87500+0=0+4000V\\\\4000V=87500\\\\V=\frac{87500}{4000}\\\\V=21.875\ m/s$

Therefore, the velocity of the truck is 21.875 m/s.

7 0

3 years ago

What would most likely cause the future acceleration of the expansion of the universe

CaHeK987 [17]

The answer is dark energy. This is the energy in the universe that opposes the gravitational attraction of matter in the universe. Initially, cosmologists had thought that the universe was decelerating due to the gravitational attraction between matter in the universe after the big bang. However, using the Doppler shift effect, evidence was gathered on the nature of the expansion of the universe.

5 0

3 years ago

NASA is conducting a test with the Perseverance Rover to investigate the gravity on Mars. They test a pendulum with a length of

Sergio039 [100]

Answer:

NASA lands Perseverance rover on the Mars surface, carrying the first helicopter for another planet. NASA successfully landed its fifth robotic rover on Mars on Thursday, with the U.S. space agency confirming that Perseverance touched down safely on the red planet's surface.

Explanation:

7 0

3 years ago

What is the net force on the box? Be sure to specify direction. 15 N 10 N