How do temperature changes lead to solubility changes for salt dissolved in water? (1 point)

A 62.0-kg skier is moving at 6.30 m/s on a frictionless, horizontal, snow-covered plateau when she encounters a rough patch 4.90

Klio2033 [76]

Here are the missing questions:
(a) How fast is the skier moving when she gets to the bottom of the hill?
(b) How much internal energy was generated in crossing the rough patch?
Part A
The initial kinetic energy of the skier is:
$E_{k0}=m\frac{v_0^2}{2}$
Part of this energy is then used to do work against the force of friction. Force of friction on the horizontal surface can be calculated using following formula:
$F_f=mg\mu$
The work is simply the force times the length:
$W_f=F_f\cdot L=mg\mu L$
So when the skier passes over the rough patch its energy is:
$E=E_{k0}-W_f$
When the skier is going down the skill gravitational potential energy is transformed into the kinetic energy:
$E_p=E_{k1}\\ mgh=E_{k1}$
So the final energy of the skier is:
$E_f=E_{k0}-W_f+E_{k1}\\ E_f=m\frac{v_0^2}{2}-mg\mu L+mgh=1856.86$J$
This energy is the kinetic energy of the skier:
$E_f=m\frac{v_f^2}{2}\\ v_f=\sqrt{\frac{2E_f}{m}}=7.74\frac{m}{s}$
Part B
We know that skier lost some of its kinetic energy when crossing over the rough patch. This energy is equal to the work done by the skier against the force of friction.
$E_{int}=W_f\\
E_{int}=mg\mu L=894.1$J$

4 0

4 years ago

This diagram shows about question 3 In this diagram, the forces on the runner and on the ground are equal. Why does the runner m

Dovator [93]

According to newton's third law: every action has an equal and opposite reaction, so yes the ground does move backwards. You have 4 forces acting on you at any given time: pushing force, friction force, gravity, and normal force. you push against something to propel forward, you have to overcome gravity and friction, and normal force keeps things upright to prevent them from falling into each other.

<span>If everything is motionless at every instant, and time is entirely composed of instants, then motion is impossible, so it must be an illusion.
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if you really want things to get confusing you can read up on zeno's dichotomy paradox stating that there is infinate amount of times you can divide something such as a distance traveled over time and you will stil

7 0

4 years ago

How much electromagnetic energy is contained in each cubic meter near the Earth's surface if the intensity of sunlight under cle

WITCHER [35]

Answer:

344.8 x10^-8J/m³

Explanation:

Using=> energy intensity/ speed oflight

= 1000/2.9x10^8

= 344.8 x10^-8J/m³

3 0

3 years ago

An object of mass 0.40 kg, hanging from a spring with a spring constant of 8.0 N/m, is set into an up-and-down simple harmonic m

Sergeeva-Olga [200]

Answer:

a = 2 m/s2

Explanation:

we know from newtons 2nd law

F = ma.

we also know that from hookes law we have

F = kx

equate both value of force to get value of acceleration

kx = ma,

where,

k is spring constant = 8.0 N/m

x is maximum displacement 0.10 m

m is mass of object 0.40 kg

a = \frac{kx}{m}

= \frac{8 *0 .10}{0.40}

a = 2 m/s2

5 0

3 years ago

Predict the speed of a car after 10.0 s when the car’s speed follows

andreev551 [17]

Answer:

48 m/s

Explanation:

The time is 10 seconds

The speed of the car after 10 seconds when the relationship is 4.8 m/s^2 × time can be calculated as follows

= 4.8 × 10

= 48

Hence the speed is 48 m/s

7 0

4 years ago