I don't think that 4m has anything to do with the problem.
anyway. here.
A___________________B_______C
where A is the point that the train was released.
B is where the wheel started to stick
C is where it stopped
From A to B, v=2.5m/s, it takes 2s to go A to B so t=2
AB= v*t = 2.5 * 2 = 5m
The train comes to a stop 7.7 m from the point at which it was released so AC=7.7m
then BC= AC-AB = 7.7-5 = 2.7m
now consider BC
v^2=u^2+2as
where u is initial speed, in this case is 2.5m/s
v is final speed, train stop at C so final speed=0, so v=0
a is acceleration
s is displacement, which is BC=2.7m
substitute all the number into equation, we have
0^2 = 2.5^2 + 2*a*2.7
0 = 6.25 + 5.4a
a = -6.25/5.4 = -1.157
so acceleration is -1.157m/(s^2)
An electrons transferred and compound forms
Answer:
Impulse = Average force x time of contact
Explanation:
Impulsive force is a force which is very large but applied on a body for a very small duration of time.
Impulse is given by the change in momentum of the body.
Impulse = Average force x small time interval
When padding is there, the time interval of contact is large and thus, the force exerted by the body is small.
So, when a person falls on the tile floor, there is no compression and thus, the time of contact is very small and thus the impulsive force is very large, due to which the body may damage.
So, when a person falls on the carpeted floor, there is a compression and thus, the time of contact is comparatively large and thus the impulsive force is small, due to which the body may safe.
Answer: 2.83 J/mol
Explanation:
Heat of solution, sometimes interchangeably called enthalpy of solution, is said to be the energy released or absorbed when the solute dissolves in the solvent. A solute is that which can dissolve in a solvent, to form a solution
Given
No of moles of CaCl = 7.5 mol
Total energy used = 21.2 J
Heat of solution = q/n where
q = total energy
n = number of moles
Heat of solution = 21.2 / 7.5
Heat of solution = 2.83 J/mol
Wooden spoons don't quickly heat to hot temperatures not nearly as fast as metal does. Metal conducts heat faster than wood — if the head of the spoon is in a hot liquid, the handle will get hot faster if it's made out of a metal.