All categories

3 years ago

Which of the following is an example of a chemical change

Physics

1 answer:

Karo-lina-s [1.5K]3 years ago

6 0

Rust is a chemical all the others are physical changes

You might be interested in

A 49 kg bear slides, from rest, 11 m down a lodgepole pine tree, moving with a speed of 3.3 m/s just before hitting the ground.

hichkok12 [17]

Answer:

a) $\Delta U_g=-5.3kJ$

b) $K=0.27kJ$

c) $F_f=0.45kN$

Explanation:

the gravitational potential energy is given by:

$U_g=m.g.h\\$

$\Delta U_g=m.g.h_f-m.g.h_i\\\Delta U_g=49kg*9.8m/s^2*(0m-11m)\\\Delta U_g=-5.3kJ$

The kinetic energy is given by:

$K=\frac{1}{2}m.v^2\\$

the initial kinetic energy is zero because the motion started from rest, so:

$K=\frac{1}{2}*49kg*(3.3m/s^2)^2\\K=0.27kJ$

applying the conservation of energy theorem:

$U_g-W_f=K_f\\W_f=-(\Delta K+\Delta U)\\W_F=5.3kJ-0.27kJ\\W_F=-5.0kJ$

The work done by the friction force is given by:

$W_f=F_f.h.cos(\theta)\\$

the angle of the force is 180 degrees because it's against the movement:

$F_f=\frac{W_f}{h.cos(\theta)}\\\\F_f=\frac{-5.0kJ}{11m.cos(180^o)}\\\\F_f=0.45kN$

8 0

4 years ago

What force must be used to do 224 Joules of work on an object over a distance of 32 meters?

cestrela7 [59]

7.625 Newtons

work = force× distance
Newtons is an accepted value for force

so take the total 224 joules and decide by distance 32 meters to find force in Newtons

4 0

4 years ago

Appliances connected so that they form a single pathway for

Serga [27]

<h2>Question:</h2>

Appliances connected so that they form a single pathway for charges to flow are connected in a(n)

<h2>Answer:</h2>

<u>A</u><u>.</u><u> </u><u>Series</u><u> </u><u>circuit</u><u> </u>

<h2><u>#CARRYONLEARNING</u><u> </u></h2><h2><u>#STUDYWELL</u><u> </u></h2>

6 0

3 years ago

What is an RC circuit?

cupoosta [38]

Is a circuit with both a resistor (R) and a capacitor (C). RC circuits are frequent element in electronic devices. They also play an important role in the transmission of electrical signals in nerve cells.

Hope this helps!

8 0

3 years ago

Which statements best describe the atoms of the gas neon? Check all that apply.

Anni [7]

What are the statements?

5 0

3 years ago

Read 2 more answers