All categories

2 years ago

A 66.5-kg hiker starts at an elevation of 1270 m and climbs to the top of a peak 2660 m high.

Physics

1 answer:

anyanavicka [17]2 years ago

8 0

Answer

given,

mass of the hiker = 66.5 kg

elevation of the hiker,h₁ = 1270 m

elevation of top peak,h₂ = 2660 m

a) Change in potential energy

Δ PE = m g h₂ - m g h₁

Δ PE = m g (h₂ - h₁)

Δ PE = 66.5 x 9.8 x (2660 - 1270)

Δ PE = 905863 J

b) Minimum work require by the hiker will be equal to Δ PE = 905863 J

c) yes, it can be more than this, if friction is present on the surface.

You might be interested in

Which pair of equations can describe the path of a particle moving with an acceleration that is perpendicular to the velocity of

antoniya [11.8K]

Answer:

The question clearly describes the circular motion.

The circular motion equation is

$a_{radial} = \frac{v^2}{r}$

The path of the particle is circular.

Explanation:

In circular motion, the radial acceleration is always towards the center and constant in magnitude. Furthermore, the velocity of the circular motion is always tangential to the circle, that is it is always perpendicular to the radius, hence the acceleration.

6 0

2 years ago

By using fossils and matching layers rock layers can be correlated to eachother.

bija089 [108]

I think that the answer to that is true hope that helps

4 0

3 years ago

Read 2 more answers

Which of the following cars have the most kinetic energy

faltersainse [42]

<h2>Hey There!</h2><h2>_____________________________________</h2><h2>Answer:</h2>

$\huge\boxed{OptionA}$

mass = 4 kg

velocity = 5 m/s^2

<h3 /><h3>Orange truck:</h3>

Mass= 2kg

Velocity = 7m/s^2

mass = 6 kg

velocity = 4m/s^2

<h3 /><h3>Green Car:</h3>

Mass = 8 kg

Velocity = 3 m/s^2

<h2>_____________________________________</h2><h2>SOLUTION:</h2>

By the equation of kinetic energy,

K.E = $\frac{1}{2} mv^2$

Where,

K.E is kinetic energy

m is mass

v is velocity

<h2>_____________________________________</h2><h3>Kinetic energy of Blue car:</h3>

Directly substitute the variables in the equation,

K.E = $\frac{1}{2}x4x5^2$

Simplify the equation,

K.E = 50 J

<h2>_____________________________________</h2><h3>Kinetic Energy of Silver Car:</h3>

Directly substitude the variable in the equation,

K.E = $\frac{1}{2}x6x4^2$

Simplify the equation,

K.E = 48J

<h2>_____________________________________</h2><h3>Kinetic Energy of Green Car:</h3><h3 />

Substitute the variables in the equation,

K.E = $\frac{1}{2}x8x3^2$

Simplify the Equation,

K.E = 36J

<h2>_____________________________________</h2><h3>Kinetic Energy of Orange Truck:</h3><h3 />

Substitute the variable,

K.E = $\frac{1}{2}x 2x7^2$

Simplify the equation,

K.E = 49J

As you can see that the highest value of kinetic energy is of Blue SUV thus it will be out answer.

<h2>_____________________________________</h2><h2>Best Regards,</h2><h2>'Borz'</h2><h3 /><h3 /><h3 /><h3 /><h2 /><h2 />

6 0

2 years ago

A block of mass 4 kilograms is initially moving at 5m/s on a horizontal surface. There is friction between the block and the sur

emmasim [6.3K]

• Net vertical force on the block:

∑ <em>F</em> = <em>n</em> - <em>w</em> = 0

(<em>n</em> = magnitude of normal force, <em>w</em> = weight)

(<em>m</em> = mass, <em>g</em> = 9.8 m/s²)

<em>n</em> = (4 kg) (9.8 m/s²) = 39.2 N

• Net horizontal force:

∑ <em>F</em> = -<em>f</em> = <em>m a</em>

(<em>f</em> = mag. of friction, <em>a</em> = acceleration)

We have <em>f</em> = <em>µ</em> <em>n</em> = 0.5 (39.2 N) = 19.6 N, so

-19.6 N = (4 kg) <em>a</em>

<em>a</em> = -4.9 m/s²

With this acceleration, the block comes to a rest from an initial speed of 5 m/s, so that it travels a distance ∆<em>x</em> in this time such that

0² - (5 m/s)² = 2 (-4.9 m/s²) ∆<em>x</em>

∆<em>x</em> = (25 m²/s²) / (9.8 m/s²) ≈ 2.55 m ≈ 2.6 m

8 0

2 years ago

A 4kg book sits on a table and your pet hamster puts his front paws on the book and pushes down with a force of 3N. What is the

Natali [406]

There are three forces acting on the book.
1. Force due to gravity
2. Force exerted downward by the hamster
3. Normal Force in reaction to the downward forces

Since the book is not moving, the net force is zero. The summation of all forces must be zero. Then we could find the normal force which is unknown (denoted as x).

∑F = -(4 kg)(9.81 m/s2) - 3 N + x =0
∑F = -39.24 N - 3N + x =0
x = 42 N

Therefore, the normal force is 42 N.

4 0

3 years ago