Use the equations below:
P=mv
Ek=1/2mv^2
4) A wooden target of mass 2.00kg is suspended from a branch so that it swings freely. The target is hit by an arrow of mass 0.10kg travelling horizontally and the arrow embeds itself in the centre of the target. The target swings upwards, with its centre of mass rising by 0.60m. Use 9.81 as the acceleration for gravity.
A) Calculate the gain in gravitational energy by the target and arrow combination.
B) Calculate the velocity of the arrow and target immediately after the impact.
C) Calculate the velocity of the arrow immediately before the impact.
D) Determine if the collision is elastic or inelastic and why.
12 marks
please answer
This one is a really tricky one so please write out in full, and no symbols please as i dont understand when you do that just full words
I find it difficult to do algebra without symbols.
gain in potential energy = m g h
= 2.1 * 9.81 * 0.60 Joules
= 12.4 Joules
kinetic energy before = gain in potential energy
(1/2)(2.1)v^2 = 12.4 Joules
v = 3.43 m/s
momentum before collision = momentum after
0.1 * u = 2.1 * v
u = 72 m/s
It is inelastic
show that (1/2)(2.1)(3.43^2) = 12.4 is less than (1/2)(.1)(72^2) = 260 Joules
In other words most of the kinetic energy of the arrow was dissipated as heat during the collision.
PS -- "learn" means "memorize"!
I also suggest any of these basic concept books: They should be available in the UK. https://www.amazon.com/Physics-Dummies-Math-Science/dp/1119293596
Thank you so much Damon I understand all of what you have written it is so clear and thank you for the tips writeacher and the useful websites as we don use any of the symbol in my class we just use full words and numbers and just mostly talk though how to do it. Thanks again Damon
Thank you Damon for your reliability and not making fun of me not knowing some symbols.
No one's making fun. Just trying to give you the information you need to keep progressing!
From yesterday -- https://www.jiskha.com/display.cgi?id=1512471691
It looks as if "cake" needs to learn the common symbols used in math and physics:
https://en.wikipedia.org/wiki/List_of_common_physics_notations
http://jick.net/symbols/Math.html
https://en.wikipedia.org/wiki/Greek_letters_used_in_mathematics,_science,_and_engineering