B. False
Stability is determined by the ratio of neutrons and protons. Electrons are not in nucleus.
Answer:
Answer E.
For a collision to be completely elastic, there must be NO LOSS in kinetic energy.
We can go through each answer choice:
A. Since the ball rebounds at half the initial speed, there is a loss in kinetic energy. This is NOT an elastic collision.
B. A collision involving sticking is an example of a perfectly INELASTIC collision. This is NOT an elastic collision.
C. A reduced speed indicates that there is a loss of kinetic energy. This is NOT elastic.
D. The balls traveling at half the speed after the collision indicates a loss of kinetic energy, making this collision NOT elastic.
E. This collision indicates an exchange of velocities, characteristic of an elastic collision. We can prove this:
Let:
m = mass of each ball
v = velocity
We have the initial kinetic energy as:
KE = \frac{1}{2}mv^2 + 0 = \frac{1}{2}mv^2KE=21mv2+0=21mv2
And the final as:
KE = 0 + \frac{1}{2}mv^2 = \frac{1}{2}mv^2KE=0+21mv2=21mv2
<h2>Steps:</h2>
- Remember that Density = mass/volume, or D = m/v
So firstly, we have to find the volume of the rock. To do this, we need to subtract the volume of water A from the volume of the water B. In this case:
- Water A = 30 mL
- Water B = 40 mL
- 40 mL - 30 mL = 10 mL
<u>The volume of the rock is 10 mL.</u>
Now that we have the volume, we can plug that and the density of the rock into the density equation to solve for the mass.

For this, multiply both sides by 10:

<h2>Answer:</h2>
<u>Rounding to the tenths place, the mass of the rock is 36.8 g, or C.</u>
Answer:
A
-1440J
Explanation:
Hello,
This question requires us to calculate the work done on a object to move it from point A to point B
Data
Mass = 60kg
Initial velocity (V1) = 8.0m/s
Final velocity (V2) = 4.0m/s
Workdone on an object is equal to force applied on the object to move it through a particular distance.
Work done = force × distance
Force (F) = mass × acceleration
Distance = s
F = Ma
Work done = M× a × s
But a = velocity (v) / time (t)
Work done = mvs / t
But velocity = distance/ time
Work done = mv × v/
Work done = mv²
Work done = ½mv²
Workdone = ½M(V2² - V1²)
Workdone = ½ × 60 (4² - 8²)
Work done = 30 × (16 - 64)
Workdone = 30 × (-48)
Work done = -1440J
Work done = -1.44kJ
The workdone on the object is equal to -1.44kJ