Answer:
Option A
20 m/s
Explanation:
From the law of conservation of linear momentum, the sum of momentum before and after collision equals zero hence for this case also, the sum of momentum of the two cars before collision should be equal to momentum after collision.
Momentum is given as the product of mass and velocity, where velocity considers the direction. Momentum, p=mv where m is the mass of the object and v is the velocity.
Momentum before collision
Since the velocities of both cars before collision are zero hence their momentum are zero ie 0.5*0+(1*0)=0
Momentum after collision
For 0.5 Kg car, its momentum will be 0.5*-40=-20 Kg.m/s
For the 1 kg car its momentum will be 1*v=1v
v-20=0
v=20 m/s
Answer:
F = 2074.13 lb
Explanation:
Given that,
Mass of car, m = 2800 lb = 1270.059 kg
Initial speed, u = 5 mi/h = 2.2352 m/s
Final speed, v = - 1.5 mi/h = -0.67056 m/s (in opposite direction)
Time, t = 0.4 s
We need to find the magnitude of the average horizontal force (lb) exerted on the car during the impact. It can be calculated as :
or
F = -2074.13 lb
So, the required force is 2074.13 lb.
Answer:
Final velocity will be equal to 0.321 m/sec
Explanation:
We have given mass of clay model of lion 
Its speed is 0.85 m/sec, so 
Mass of another clay model 
It is given that second clay is motionless
So its velocity 
Now according to conservation of momentum
Momentum before collision will be equal to momentum after collision
So 
, here v is velocity after collision
So 
v = 0.321 m/sec
So final velocity will be equal to 0.321 m/sec
In the Periodic Table, elements with similar reactivity and similar properties are found under the same column.
In fact, elements in the same columns are said to be in the same "group", and they have the same number of valence electrons, i.e. the same number of electrons in the outermost shell. This is the main characteristics that determine how an element reacts with other elements.
For instance, Litium (Li), sodium (Na) and potassium (K) are all in the first group, and they both have 1 valence electrons. This means they can easily give away this electron to an atom of another element forming bonds with it, and therefore they have high reactivity. Instead, elements of the 8th group are called "noble gases", and they all have similar properties: they all have the outermost shell full of eletrons, so they have zero valence electrons and so they have little or no reactivity at all. Example of elements in this group are Neon (Ne) and Argon (Ar).
<span>If you have only two
data from two recording stations then you will be having a hard time finding
the correct location of the epicenter. This is because triangulation method requires
3 recording station. If you have 2 recording station, the 2 circles will
intersect at 2 points giving you 2 locations that could possibly be the
epicenter.</span>
