Ask question

Ask question

All categories

3 years ago

9

Sarah is sitting at the top of the slide in the school's playground. Which of the following changes will increase Sarah's kineti

c energy?
A

An additional child is added to the top of the slide.

B

Sarah is pushed and moves down the slide.

C

Sarah climbs down the ladder and off the slide.

D

The ladder is moved to the other side of the yard.

1 answer:

Ray Of Light [21]3 years ago

7 0

B; kinetic energy is anything in motion

You might be interested in

Can you respond this two questions, please? :

Andrews [41]

Where's the diagram for question 1?

6 0

3 years ago

Insulating materials are rated by their _____. specific heat heat index r-value temperature resistance

Leokris [45]

That would be the R-value

3 0

3 years ago

Read 2 more answers

An Atwood machine consists of two masses, mA = 6.8 kg and mB = 8.0 kg , connected by a cord that passes over a pulley free to ro

Lisa [10]

To solve this problem it is necessary to apply the concewptos related to Torque, kinetic movement and Newton's second Law.

By definition Newton's second law is described as

F= ma

Where,

m= mass

a = Acceleration

Part A) According to the information (and as can be seen in the attached graph) a sum of forces is carried out in mass B, it is obtained that,

$\sum F = m_b a$

$m_Bg-T_B = m_Ba$

$T_B = m_Bg-m_Ba$

In the case of mass A,

$\sum F = m_A a$

$T_A = m_Ag-m_Aa$

Making summation of Torques in the Pulley we have to

$\sum\tau = I\alpha$

$T_BR_0-T_AR_0=I\alpha$

$T_B-T_A=I\frac{a}{R^2_0}$

Replacing the values previously found,

$(m_Bg-m_Ba )-(m_Ag-m_Aa )=I\frac{a}{R^2_0}$

$(m_B-m_A)g-(m_B+m_A)a=I\frac{a}{R^2_0}$

$a = \frac{(m_B-m_A)g}{\frac{I}{R_0^2}+(m_B+m_A)}$

$a = \frac{(m_B-m_A)g}{\frac{MR^2_0^2/2}{R_0^2}+(m_B+m_A)}$

$a =\frac{(m_B-m_A)g}{\frac{M}{2}+(m_B+m_A)}$

Replacing with our values

$a =\frac{(8-6.8)(9.8)}{\frac{0.8}{2}+(8+6.8)}$

$a=0.7736m/s^2$

PART B) Ignoring the moment of inertia the acceleration would be given by

$a' =\frac{(m_B-m_A)g}{(m_B+m_A)}$

$a' =\frac{(8-6.8)(9.8)}{(8+6.8)}$

$a' = 0.7945$

Therefore the error would be,

$\%error = \frac{a'-a}{a}*100$

$\%error = \frac{0.7945-0.7736}{0.7736}*100$

$\%error = 2.7%$

8 0

3 years ago

In regards to mechanical energy, is energy being conserved ?

xxTIMURxx [149]

If only internal forces are doing work (no work done by external forces), then there is no change in the total amount of mechanical energy. The total mechanical energy is said to be conserved. ... In these situations, the sum of the kinetic and potential energy is everywhere the same.

7 0

2 years ago

Pls answer 9 Through 12

belka [17]

Answer:

physics,chemistry,biology,astronomy and earht sciences

principles of science are integrity of knowledge honesty,collegiality(cooperation between colleagues) objectivity and openness

examples of science are actually branches of science so those are biology,mathematics,chemistry and physics etc

science is importent to provide our basic needs and to improve our living standard.It makes our life much easier by providing different technologies.It helps in the diagnosing and treatment of a disease

4 0

3 years ago