Which of the following is the most important skill for a human resource

the coefficient of kinetic friction between a couch and the floor is 0.65. if the couch has a mass of 42 kg and you push it with

Anna [14]

Explanation:

The net force along the horizontal direction is

$\sum{F_x} = F_{applied} - f$

where f is the frictional force. We can find the frictional force by looking at the vertical forces acting on the couch:

$\sum{F_y} = N - mg = 0 \Rightarrow N = mg$

From the definition of frictional force,

$f = \mu{N} = \mu{mg} = (0.65)(42\:\text{kg})(9.8\:\text{m/s}^2)$

$\:\:\:\:= 267.5\:\text{N}$

Therefore, the net force on the couch is

$\sum{F_x} = 600\:\text{N} - 267.5\:\text{kN} = 332.5\:\text{N}$

4 0

2 years ago

3) A driver in a 1000-kg car traveling at 24 m/s slams on the brakes and skids to a stop. If the coefticient of friction between

Natali5045456 [20]

Answer:

A) 37 m

Explanation:

The car is moving of uniformly accelerated motion, so the distance it covers can be calculated by using the following SUVAT equation:

$v^2 -u^2 = 2ad$ (1)

where

v = 0 m/s is the final velocity of the car

u = 24 m/s is the initial velocity

a is the acceleration

d is the length of the skid

We need to find the acceleration first. We know that the force responsible for the (de)celeration is the force of friction, so:

$F=ma=-\mu mg$

where

m = 1000 kg is the mass of the car

$\mu = 0.80$ is the coefficient of friction

a is the deceleration of the car

g = 9.8 m/s^2 is the acceleration due to gravity

The negative sign is due to the fact that the force of friction is against the motion of the car, so the sign of the acceleration will be negative because the car is slowing down. From this equation, we find:

$a=-\mu g$

And we can substitute it into eq.(1) to find d:

$v^2 -u^2 = 2(\-mu g) d\\d= \frac{v^2-u^2}{-2 \mu g}=\frac{0-(24 m/s)^2}{-2(0.80)(9.8 m/s^2)}=36.7 m \sim 37 m$

7 0

3 years ago

una onda longitudinal tiene una frecuencia de 200 hz y una longitud de onda de 4.2m ¿cual es la rapidez de la onda?

swat32

Answer:

v = 8.4 m/s

Explanation:

The question ays, "A longitudinal wave has a frequency of 200 Hz and a wavelength of 4.2m. What is the speed of the wave?".

Frequency of a wave, f = 200 Hz

Wavelength = 4.2 cm = 0.042 m

We need to find the speed of the wave. The formula for the speed of a wave is given by :

$v=f\lambda\\\\v=200\times 0.042\\\\=8.4\ m/s$

So, the speed of the wave is equal to 8.4 m/s.

4 0

2 years ago

When attempting to determine the coefficient of kinetic friction, why is it necessary to move the block with constant velocity

Readme [11.4K]

Answer:

Explanation:

In order to measure the coefficient of friction , we apply external force to move the body . When external force comes in motion , we adjust the external force so that it moves with zero acceleration or uniform velocity . In this case external force becomes equal to kinetic frictional force and then net force becomes zero because

net force = mass x acceleration = m x 0 = 0

Now frictional force = μ mg where μ is coefficient of kinetic friction

so F = μ mg where F is external force applied

μ = F / mg

Hence , to make external force equal to frictional force , it is necessary to make acceleration of body zero .

4 0

3 years ago

in a one dimensional collision, a 4kg object and 6 kg onject have initial velocity. calculate the magnitude of impulse

Greeley [361]

in a one dimensional collision, a 4kg object with 5ms^1 and 6 kg object with 2ms^1 have initial velocity, the magnitude of impulse is 12 , 18

given,

mass 1 = 4kg

mass 2 = 6kg

velocity 1 = 5ms^1

velocity 2 = 2ms^1

impulse 1 = 4*(5-2)

= 12

Impulse 2 = 6*(5-2)

= 18

Learn more about impulse here

brainly.com/question/16980676

#SPJ4

8 0

1 year ago