The average velocity = Displacement between two points/ Time taken for that displacement
In this case An ion's position vector is initially r = 8.0 i - 4.0 j + 3.0 k, and 8.0 s later it is r = 4.0 i + 8.0 j - 6.0 k
So, displacement = 4.0 i + 8.0 j - 6.0 k - (8.0 i - 4.0 j + 3.0 k)
= -4.0 i + 12.0 j - 9.0 k
So velocity, V = (-4.0 i + 12.0 j - 9.0 k)/8
= -0.5 i + 1.5 j - 1.125 k
So average velocity during 8 seconds = -0.5 i + 1.5 j - 1.125 k
Answer:
The time it will take to cook three hot dogs simultaneously is 2.5 minutes
Explanation:
Here we have, the Energy of electric heating given by Joule heating that is;
P = IV = 120×10 = 1200 J/s = 1.2 kJ/s
Since the energy required to cook one hotdog = 60.0 kJ we have
Energy required to cook three hot dogs = 3 × 60.0 kJ = 180.0 kJ
Therefore, the time required to cook the three hot dogs is
(180.0 kJ)/(1.2 kJ/s) = 150 s
The time it takes to cook three hot dogs simultaneously is
150 seconds or 150/60 minutes which is 2 minutes 30 seconds or 2.5 minutes
Answer:

Explanation:
Two identical sticky masses m are moving in the xy-plane, with their momenta at an angle of φ with one another. They are each moving at the same speed v when they collide at the origin of the coordinates and stick together. After the collision, the masses move at an angle −θ2 with respect to the +x axis at speed v2 .1. What was the angle φ?
from the principle of momentum
In a system of colliding bodies,we know that the total momentum before collision will equal to the total momentum after collision.
Take note that momentum is the product of mass and velocity
momentum before collision=momentum after collision
mass, m
u=initial velocity of the identical masses
v2=the common velocity after the collision
Note that the collision is inelastic , since they both moved with the same velocity
umcosφ+umcosφ=(m+m)v2cos−θ2
2mucosφ=2mv2cos−θ2

Answer:
Most metals are in the liquid state at room temperature.<u>False</u><u>.</u>
Explanation:
it needs excess heat except mercury and lithium.
In a completely inelastic collision, the two objects stick together after the collision.