How much work is accomplished when a force of 400 N pushes a box across the floor for a distance of 10 meters?

A concept is the general idea of objects, events, animals, or people based on common features, traits, or characteristics.

salantis [7]

Answer:

True.

Explanation:

Science can be defined as a branch of intellectual and practical study which systematically observe a body of fact in relation to the structure and behavior of non-living and living organisms (animals, plants and humans) in the natural world through experiments.

A concept is the general idea of objects, events, animals, or people based on common features, traits, or characteristics. It is typically considered to be an abstract idea or general notion that is formed by the mental combination of all the characteristics pertaining to the idea.

Generally, concepts are used in the problem-solving process as it serves as a benchmark or yardstick for the solutions. Some examples of concepts in physics are conservation of energy and momentum, electromagnetic waves, heat, motion and forces, electricity and magnetism, gravity, etc.

7 0

3 years ago

How does the de broglie wavelength of an electron change if its momentum increases?

Virty [35]

Answer:

The De Broglie wavelength decreases

Explanation:

The relationship between the De Broglie wavelength of a particle and its momentum is given by

$\lambda=\frac{h}{p}$

where

$\lambda$ is the De Broglie wavelength of the particle

h is the Planck constant

p is the momentum of the particle

As we see from the formula, there is an inverse relationship between the De Broglie's wavelength and the momentum. Therefore, we can conclude that:

- if the momentum of the electron increases,

- its De Broglie wavelength will decrease

and vice-versa.

3 0

3 years ago

A train travels 59 kilometers in 3 hours, and then 74 kilometers in 5 hours. What is its average speed?

dybincka [34]

Average speed = (total distance) / (total time)

Total distance = 59 km + 74 km = 133 km

Total time = 3 hrs + 5 hrs = 8 hrs

Average speed = (133 km) / (8 hrs) = 16.625 km/hr

3 0

3 years ago

7. A roller coaster’s velocity at the top of a hill is 10 m/s. Two seconds later it reaches the bottom ofthe hill with a velocit

zheka24 [161]

Answer:

7) $a=8m/s^2$

8) $a=-5m/s^2$

9) $a=-1.5m/s^2$

10) $v=29.4m/s$

Explanation:

For the problems 7, 8 and 9 we just apply the definition of acceleration, since no more information is given, which is:

$a=\frac{\Delta v}{\Delta t}=\frac{v_f-v_i}{t_f-t_i}$

So for each problem we will have:

7) $a=\frac{26m/s-10m/s}{2s}=8m/s^2$

8) $a=\frac{10m/s-25m/s}{3s}=-5m/s^2$

9) $a=\frac{0m/s-15m/s}{10s}=-1.5m/s^2$

For the problem 10, we use the equation of velocity in accelerated motion:

$v=v_0+at$

Since the ball starts from rest and the acceleration is that of gravity (we take the downward direction positive), we have:

$v=(0m/s)+(9.8m/s)(3s)=29.4m/s$

5 0

3 years ago

An applied pulling force of 100 N is used to accelerate an object to the right along a rough surface that offers 40 N of frictio

blondinia [14]

Answer:

$9.8 m/s^2$

Explanation:

First of all, we analyze the vertical direction.

Along this direction, the object is in equilibrium, so its acceleration is zero, and therefore the net force on it is zero. There are only two forces acting on the object vertically: the weight, W (downward), and the normal force, N (upward), and since the net force must be zero, we can write

$W=N$