a. How high did the car climb up the hill after bouncing? Did it go higher lower or the same height as the drop position?

Why do waves in a tank are 10 cm long if they pass a point at a rate of 3.75 waves per second what is the speed in m/s?

AURORKA [14]

Answer: 0.0267m/s

Explanation: Wave speed in m/s

Speed = Distance/Time

Substitute the given values into the formula

Speed = 0.1/3.75

Speed = 0.0267m/s

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2 years ago

Classify each process according to whether it does or does not produce a new substance.

AlexFokin [52]

The processes under chemical change are: cooking an egg, fireworks exploding, and rusting of a metal tool.

The processes under physical change are: melting ice, evaporating puddle of water, and dissolving of salt in water.

Given:

The following process:

cooking an egg
melting ice
fireworks exploding
evaporating puddle of water
rusting of a metal tool
Dissolving of salt in water

To find:

The classify the processes in whether it does or does not produce a new substance.

Solution:

Chemical change is the change when a new substance is formed due to a change in the chemical composition of the substance.
Physical change is the change in which no change in chemical composition takes place and the identity of the substance remains the same.

Cooking an egg

Chemical change, due to change in atomic arrangement egg get solidified on cooking, a new substance is formed.

Melting ice

Physical change, change in the state of matter is taking from solid to liquid, no new substance is formed.

Firework exploding

Chemical change. formation of carbon dioxide gas and sound energy, anew substance formed

Evaporating puddle of water

Physical change, change in the state of matter is taking from liquid to gas, no new substance is formed.

Rusting of metal tool

Chemical change, formation of oxides on the surface of the metal tool due to reaction between air and metal, a new substance is formed.

Dissolving of salt in water

Physical change, ions of salt in the solid state are changing into aqueous ions with no formation of new substance, no new substance is formed.

The processes under chemical change are: cooking an egg, fireworks exploding, and rusting of a metal tool.

The processes under physical change are: melting ice, evaporating puddle of water, and dissolving of salt in water.

Learn more about physical change and chemical change here:

brainly.com/question/864557?referrer=searchResults

brainly.com/question/13316655?referrer=searchResults

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3 years ago

A 75-m-long train begins uniform acceleration from rest. the the train has a speed of 23 m/s when it passes a railway worker tan

Lapatulllka [165]

Answer:

acceleration a = 1.04 m/s2

Explanation:

Assume the train has a speed of 23m/s when the last car passes the railway workers. Once this happens the last car would have traveled a total distance of the 180m distance between the railway worker standing 180 m from where the front of the train started plus the 75m distance from the first car to the last car:

s = 75 + 180 = 255 m

We can use the following equation of motion to find out the distance traveled by the car:

$v^2 - v_0^2 = 2as$ where v = 23 m/s is the velocity of the car when it passes the worker, $v_0$ = 0m/s is the initial velocity of the car when it starts, a m/s2 is the acceleration, which we are looking for.