All categories

2 years ago

Explain the forces that keep a rock balanced on a tiny pedestal. Please help me with this!

1 answer:

8 0

Normal force for the rock because that makes an object stable at its position.
static friction because micro-welts hold its particle on its position so it doesn't change in position by a potential energy. Gravity makes it stay on the ground because its force attraction between an object and the earth.
Hope this helps <span />

You might be interested in

According to the three laws of planetary motion, planetary orbits are in the shape of a/an

Talja [164]

<span>According to the three laws of planetary motion, planetary orbits are in the shape of an "Ellipse"

In short, Your Answer would be Option B

Hope this helps!</span>

8 0

3 years ago

If anyone here can help me with physics please comment. its about coulombs law

Minchanka [31]

I may be able to help you with This subject

3 0

3 years ago

0.250 moles of gas are in a piston.The gas does 109 J of work while 240 J of heat are added. What is the change in internal ener

irina [24]

Answer:

+131Joules

Explanation:

Energy can be expressed using below expresion.

ΔE = (q + w).........eqn(1)

q will be + be if heat is gained hence, q= 240 J

work "w" will be - ve if work is done by the system, hence w= -109 J

Then substitute into eqn(1)

Change in Internal energy=

= (240 -109 )

= +131J

6 0

3 years ago

You pull on a spring whose spring constant is 22 N/m, and stretch it from its equilibrium length of 0.3 m to a length of 0.7 m.

Liono4ka [1.6K]

Answer:

W= 4.4 J

Explanation

Elastic potential energy theory

If we have a spring of constant K to which a force F that produces a Δx deformation is applied, we apply Hooke's law:

F=K*x Formula (1): The force F applied to the spring is proportional to the deformation x of the spring.

As the force is variable to calculate the work we define an average force

$F_{a} =\frac{F_{f}+F_{i} }{2}$ Formula (2)

Ff: final force

Fi: initial force

The work done on the spring is :

W = Fa*Δx

Fa : average force

Δx : displacement

$W = F_{a} (x_{f} -x_{i} )$ :Formula (3)

$x_{f}$ : final deformation

$x_{i}$ :initial deformation

Problem development

We calculate Ff and Fi , applying formula (1) :

$F_{f} = K*x_{f} =22\frac{N}{m} *0.7m =15.4N$

$F_{i} = K*x_{i} =22\frac{N}{m} *0.3m =6.6N$

We calculate average force applying formula (2):

$F_{a} =\frac{15.4N+6.2N}{2} = 11 N$

We calculate the work done on the spring applying formula (3) : :

W= 11N*(0.7m-0.3m) = 11N*0.4m=4.4 N*m = 4.4 Joule = 4.4 J

Work done in stages

Work is the change of elastic potential energy (ΔEp)

W=ΔEp

ΔEp= Epf-Epi

Epf= final potential energy

Epi=initial potential energy

$E_{pf} =\frac{1}{2} *k*x_{f}^{2}$

$E_{pi} =\frac{1}{2} *k*x_{i}^{2}$

$E_{pf} =\frac{1}{2} *22*0.7^{2} = 5.39 J$

$E_{pf} =\frac{1}{2} *22*0.3^{2} = 0.99 J$

W=ΔEp= 5.39 J-0.99 J = 4.4J

4 0

2 years ago

Which statement below could be used as evidence to support the claim that using nuclear energy to produce electricity is better

Montano1993 [528]

Answer:

Explanation:

C would make the most sense because the problem with fossil fuels is the fact that it emits greenhouse gases that warm up the earth over a long period of time as the climate has changed because of it.

7 0

2 years ago