Answer:
- Here we use the conservation of momentum theorem.
- m stands for mass, and v stands for velocity. The numbers refer to the respective objects.
- m1v1 + m2v2 = m1vf1 + m2vf2
- Since the equation is perfectly inelastic, the final velocity of both masses is the same. Let’s account for this in our formula.
- m1v1 + m2v2 = vf(m1 + m2)
<u>Let’s substitute in our givens.</u>
(0.002 kg)(700 m/s) + (5 kg)(0 m/s) = vf(0.002 kg + 5 kg)
I assume you are proficient in algebra I, so I will not include the steps to simplify this equation.
Note that I have considered the bullet’s velocity to be in the positive direction,
The answer is vf = 0.280 m/s
Answer: thickness h = 0.014cm
Question: In the manufacturing of computer chips, cylinders of silicon are cut into thin wafers that are 3.30 inches in diameter and have a mass of 1.50 g of silicon. How thick (mm) is each wafer if silicon has a density of 2.33 g/cm 3 ? (The volume of a cylinder is V=πr 2 h )
Explanation:
The volume of a cylinder is
Volume V = πr^2h ....1
The density of a material is
Density D = mass m / volume V
D = m/V ....2
Since m and D are given, we can make V the subject of formula.
V = m/D ....3
From equation 1, we need to derive the thickness h of the cylindrical silicon.
h = V/πr^2 .....4
Substituting equation 3 into 4
h = (m/D)/πr^2 .....5
Given.
mass m = 1.50g
density D = 2.33g/cm^3
radius r = diameter/2 = 3.00in/2 = 7.62/2 cm = 3.81cm
Substituting the given values into the equation
h = (1.5/2.33)/(π ×3.81^2)
thickness h = 0.014cm
Railroad steel wheels. Bowling ball.
Answer:
yi = Initial height of the helicopter
yf = final height of the helicopter
vyi = component of the initial vertical velocity of the helicopter
g = gravity constant (9.8m/s^2)
yf = yi + vyideltat - 1/2gt^2
0m = 1000m + (15m/2)deltat - 1/2(9.8m/s^2)t^2
-1000m = (15m/s)t - (-4.9m/s^2)t^2
Use the quadratic formula
4.8t^2 - 15t - 1000 = 0
t1 = 15.75s and t2 = -12.65
t2 is rejected, time can't be negative
Thus, it takes 15.75s before the package strikes the ground.
