Kim took 5 hours to complete a journey with an average speed

Part 1 :

dybincka [34]

Answer:

1. 218.55 N

2. $30.96^{o}$

3. $2.1 m/s^{2}$

Explanation:

Part 1;

Net force $F=mg sin \theta$ where m is mass, g is gravitational force and $\theta$ is the angle of inclination

$F= 46*9.8*sin 29^{o}= 218.55N$

Frictional force, $F_{r}$ is given by

$F_{r} = \mu_{s}mg cos \theta$ where $\mu_{s}$ is the coefficient of static friction

$F_{r} = 0.6*46*9.8 cos 29$

$F_{r}=236.57N$

Since $F_{r}>F$ , therefore, the block doesn’t slip and the frictional force acting is mgh=218.55N

Part 2.

Using the relationship that

Frictional force $F_{s} = \mu_{s} mg cos \theta$

$mg sin \theta =\mu_{s} mg cos \theta$

$\mu_{s}= \frac {sin \theta}{cos \theta}$

$\mu_{s}= tan \theta$

The maximum angle of inclination $\theta = tan^{-1} \mu_{s}$

$\theta = tan^{-1} (0.6)$

$\theta= 30.96^{o}$

Part 3:

Net force on the object is given by

$ma = mg sin 38 - \mu_{k} mg cos 38$ where $\mu_{k}$ is the coefficient of kinetic friction

$a = g ( sin 38 - \mu_{k} cos 38 )$

= 9.8 ( sin 38 - (0.51) cos 38 )

= $2.1m/s^{2}$

7 0

3 years ago

Oceans and other bodies of water are found on which layer of earth

satela [25.4K]

Answer:

They are found in the Hydrosphere

Explanation:

holped it helped!!

7 0

2 years ago

A basketball of mass 0.23kg is thrown horizontally against a rigid vertical wall with a velocity of 20m/s. It rebounds with a ve

Anna11 [10]

Answer:

$8.1\:\mathrm{Ns}$

Explanation:

The impulse-momentum theorem gives the impulse on an object to be equal to the change in momentum of that object. Since mass is maintained, the change in momentum of the basketball is:

$\Delta p = m\Delta v$ , where $m$ is the mass of the basketball and $\Delta v$ is the change in velocity.

Since the basketball is changing direction, its total change in velocity is:

$\Delta v = 20-(-15)=35\:\mathrm{m/s}$ .

Therefore, the basketball's change in momentum is:

$\Delta p = m\Delta v = 0.23\cdot 35= 8.05=8.1\:\mathrm{kg\cdot m/s}$ .

Thus, the impulse on the basketball is $\fbox{$8.1\:\mathrm{Ns}$}$ (two significant figures).

7 0

2 years ago

What is NOT a 21st-century skill that can help a person thrive today?

Soloha48 [4]

Ability to memorize and regurgitate information on tests is the skill that can’t help a person to thrive today in this modern 21st century.

Answer: Option D

<u>Explanation:</u>

Thriving in this modern 21st century is not as easy as it used to be in the early 20th and 19th centuries. So there is a need to develop skills like implementing one's knowledge to real-world structures which will sure help a person to understand and explore more.

Statement B also will sure be helpful to survive in modern society and a person can also improve his/her critical thinking, problem solving and other skills to thrive through this century.

But even though memorizing and regurgitating information can help you get good grade it will never be that helpful in other ways, So option D can be concluded as the right answer.

3 0

2 years ago

What are the four components that can be derived from a unit of blood?

Katen [24]

Within that unit of blood, you are going to have plasma, white blood cells, red blood cells, and platelets.

7 0

2 years ago