Ask question

Ask question

All categories

2 years ago

15

A 2.6 kg rock is dropped from a height of 10 m. With what speed will it strike the ground. Ignore air resistance. Solve using co

nservation of energy (start with Ebefore = Eafter).

1 answer:

timurjin [86]2 years ago

5 0

Answer:

$mgh = \frac{1}{2} m {v}^{2} \\ v = \sqrt{2gh} \\ = \sqrt{2 \times 9.8 \times 10} \: m. {s}^{ - 1}$

You might be interested in

Kevin is refinishing his rusty wheelbarrow. He moves his sandpaper back and forth 45 times over a rusty area, each time moving a

dmitriy555 [2]

W = _|....F*dx*cos(a)........With F=force, x=distance over which force acts on object,
.......0.............................and a=angle between force and direction of travel.

Since the force is constant in this case we don't need the equation to be an integral expression, and since the force in question - the force of friction - is always precisely opposite the direction of travel (which makes (a) equal to 180 deg, and cos(a) equal to -1) the equation can be rewritted like so:

W = F*x*(-1) ............ or ............. W = -F*x

The force of friction is given by the equation: Ffriction = Fnormal*(coeff of friction)

Also, note that the total work is the sum of all 45 passes by the sandpaper. So our final equation, when Ffriction is substituted, is:

W = (-45)(Fnormal)(coeff of friction)(distance)
W = (-45)...(1.8N).........(0.92).........(0.15m)
W = ................-11.178 Joules

5 0

3 years ago

Derive the explicit rule for the pattern <br> 3, 0, -3, -6, -9,

pickupchik [31]

It is the last number minus 3

8 0

3 years ago

Read 2 more answers

A skier is accelerating down a 30.0-degree hill at 3.80 m/s^2.

Bond [772]

Answer:

ax = -3.29[m/s²]

ay = -1.9[m/s²]

Explanation:

We must remember that acceleration is a vector and therefore has magnitude and direction.

In this case, it is accelerating downwards, therefore for a greater understanding we will make a diagram of said vector, this diagram is attached.

$a_{x}=-3.8*cos(30) = -3.29 [m/s^{2}]\\ a_{y}=-3.8*sin(30) = -1.9 [m/s^{2}]$

3 0

2 years ago

An automobile to be transported by ship is raised 8.2m above the dock. If it's GPE is 63,405 J what is the car's mass?

Pepsi [2]

Answer:

m = 788.2[kg]

Explanation:

The potential energy of a body is defined as the product of mass by gravitational acceleration by height. And it can be calculated by means of the following equation.

$E_{pot}=m*g*h$

where:

Epot = potential energy = 63405 [J]

m = mass [kg]

g = gravity acceleration = 9.81[m/s²]

h = elevation = 8.2[m]

Now replacing:

$63405=m*9.81*8.2\\m=788.2[kg]$

5 0

3 years ago

T/F climate can change quickly

Vitek1552 [10]

bhdfbvhfdbvhhfhvfhdf vfdhybvghbhdf

4 0

3 years ago