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Describe how a crumple zone on a car reduces injury to the driver in a crash.

During a crash the velocity of the car is reduced to zero. The deceleration of the car exerts a force on the driver causing injury. Without a crumple zone the change in velocity is instantaneous therefore a ...
TL
Answered by Thomas L. • Physics tutor
3909 Views

Explain the trend in reactivity of group 1 metals.

Going down the 1st column of the periodic table the group 1 metal have increasing numbers of electrons.All group 1 metals have a single electron in their outer shell and with an increasing number of electron...
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Answered by Thomas L. • Chemistry tutor
4776 Views

What is the difference between "por" and "para"?

They are both prepositions that can be translated as "for" in English. As a rule, you can think of "por" as anything that explains the reason or the means/way through which you do somethi...
RS
Answered by Rosa S. • Spanish tutor
2849 Views

Peter is 180cm tall, correct to 2 significant figures. Alice is 150cm tall, correct to 2 significant figures. What is the upper and lower bound of the difference in their heights?

Upper bound of Peter's height = 185cmLower bound of Peter's height = 175cmUpper bound of Alice's height = 155cmLower bound of Alice's height = 145cmFor the upper bound of the difference, we want the upper bo...
JT
Answered by James T. • Maths tutor
4206 Views

Explain the difference between diffusion and active transport with examples.

Diffusion is the passive process by which molecules move across a semi permeable membrane down their concentration gradient from an area of high concentration to low concentration. An example is gaseous exch...
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Answered by Sarah M. • Biology tutor
9476 Views