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
Brut [27]
4 years ago
7

The skateboarder has a mass of 100 kg. When traveling downward from E to D, he reaches a velocity of 11 m/s. Calculate his kinet

ic energy at D (explain work and include units please).
(KE= ½ mv2)

Physics
1 answer:
patriot [66]4 years ago
6 0

6050 J is the kinetic energy at D

<u>Explanation:</u>

In physics, the object's kinetic energy (K.E) defined as the energy it possesses during movement. It can be defined as the required work to accelerate a certain body weight in order to rest at a certain speed. When the body receives this energy as it speeds up (accelerates), it retains this energy unless speed varies. The equation is given as,

           K . E=\frac{1}{2} \times m \times v^{2}

Where,

m - mass of an object

v - velocity of the object

Here,

Given data:

m  = 100 kg

v = 11 m/s

By substituting the given values in the above equation, we get

            K . E=\frac{1}{2} \times 100 \times(11)^{2}=\frac{1}{2} \times 100 \times 121=\frac{12100}{2}=6050\ \mathrm{J}

You might be interested in
Difference between work done against gravity and friction​
mario62 [17]
Mark Brainliest please


Friction is a nonconservative force. Therefore work done against friction cannot be stored as potential energy and later converted back to kinetic the way work against gravity can.

Gravity always pulls objects such as a desk, book or person down. Thus, when you jump, gravity causes you to land on the ground. Friction, however, doesn't pull objects down. ... Instead friction occurs when something like a machine or individual pulls a sliding object in the opposite direction of another object.


Friction and gravity exist in every aspect of a person’s life. For example, almost every movement you make, such as walking and running, involves friction. When you throw a ball up, gravity causes the ball to fall down. A person sliding a book across a table creates friction. Nevertheless, differences between gravity and friction also exist. Force affects gravity and friction in different ways.
8 0
3 years ago
A child in a tree house uses a rope attached to a basket to lift a 24 N dog upward through a distance of 4.9 m into the house.
jenyasd209 [6]
<h3>Answer:</h3>

117.6 Joules

<h3>Explanation:</h3>

<u>We are given;</u>

  • Force of the dog is 24 N
  • Distance upward is 4.9 m

We are required to calculate the work done

  • Work done is the product of force and distance
  • That is; Work done = Force × distance
  • It is measured in Joules.

In this case;

Force applied is equivalent to the weight of the dog.

Work done = 24 N × 4.9 m

                  = 117.6 Joules

Hence, the work done in lifting the dog is 117.6 Joules

3 0
3 years ago
A stuntman jumps from the roof of a building to the safety net below. How far has the stuntman fallen after 1.6 seconds?
Fantom [35]
How tall is the building?
u need to divide the height by 1.6 to get your answer
6 0
3 years ago
A car traveling with constant speed travels 150 km in 7200s. What is the speed of the car?
LiRa [457]
Speed= distance/time
Speed= 150000m/7200s=20.83m/s(cor.to.2d.p.)
7 0
3 years ago
A monatomic gas is adiabatically compressed to 0.250 of its initial volume. Do each of the following quantities change?
Len [333]

Answer:

Given that

V2/V1= 0.25

And we know that in adiabatic process

TV^န-1= constant

So

T1/T2=( V1 /V2)^ န-1

So = ( 1/0.25)^ 0.66= 2.5

Also PV^န= constant

So P1/P2= (V2/V1)^န

= (1/0.25)^1.66 = 9.98

A. RMS speed is

Vrms= √ 3RT/M

But this is also

Vrms 2/Vrms1= (√T2/T1)

Vrms2=√2.5= 1.6vrms1

B.

Lambda=V/4π√2πr²N

So

Lambda 2/lambda 1= V2/V1 = 0.25

So the mean free path can be inferred to be 0.25 times the first mean free path

C. Using

Eth= 3/2KT

So Eth2/Eth1= T2/T1

So

Eth2= 2.5Eth1

D.

Using CV= 3/2R

Cvf= Cvi

So molar specific heat constant does not change

5 0
3 years ago
Read 2 more answers
Other questions:
  • You observe that a negatively charged plastic pen repels a charged piece of magic tape. You then observe that the same piece of
    15·1 answer
  • An imbalance of _____________ causes an object to be charged.
    5·1 answer
  • An astronaut on a distant planet wants to determine its acceleration due to gravity. the astronaut throws a rock straight up wit
    5·1 answer
  • Explain how rock D is the best rock
    5·1 answer
  • The intensity of the sound from a certain source is measured at two points along a line from the source. The points are separate
    7·1 answer
  • Derive a relation between time period anf frequency of a wave
    7·1 answer
  • Calculate the final velocity right after a 117 kg rugby player who is initially running at 7.45 m/s collides head‑on with a padd
    12·1 answer
  • If two charged balloons are 24cm apart and they feel a force of electrical repulsion of 20N, what would the force of electrical
    14·1 answer
  • Convert 0.700 to scientific notation
    10·1 answer
  • After a meal.
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!