A 0.100-kg ball is thrown with a speed of 20.0 m/s at an angle of 30.0° with the horizontal. Find

A 35 g steel ball is held by a ceiling-mounted electromagnet 4.0 m above the floor. A compressed-air cannon sits on the floor, 4

HACTEHA [7]

Answer:

7.9 m/s

Explanation:

When both balls collide, they have spent the same time for their motions.

Motion of steel ball

This is purely under gravity. It is vertical.

Initial velocity, u = 0 m/s

Distance, s = 4.0 m - 1.2 m = 2.8 m

Acceleration, a = g

Using the equation of motion

$s = ut+\frac{1}{2}at^2$

$2.8 \text{ m} = 0+\dfrac{gt^2}{2}$

$t = \sqrt{\dfrac{5.6}{g}}$

Motion of plastic ball

This has two components: a vertical and a horizontal.

The vertical motion is under gravity.

Considering the vertical motion,

Initial velocity, u = ?

Distance, s = 1.2 m

Acceleration, a = -g (It is going up)

Using the equation of motion

$s = ut+\frac{1}{2}at^2$

$1.2\text{ m} = ut-\frac{1}{2}gt^2$

Substituting the value of t from the previous equation,

$1.2\text{ m} = u\sqrt{\dfrac{5.6}{g}}-\dfrac{1}{2}\times g\times\dfrac{5.6}{g}$

$u\sqrt{\dfrac{5.6}{g}} = 4.0$

Taking g = 9.8 m/s²,

$u = \dfrac{4.0}{0.756} = 5.29 \text{ m/s}$

This is the vertical component of the initial velocity

Considering the horizontal motion which is not accelerated,

horizontal component of the initial velocity is horizontal distance ÷ time.

$u_h = \dfrac{4.4\text{ m}}{0.756\text{ s}} = 5.82\text{ m/s}$

The initial velocity is

$v_i = \sqrt{u^2+u_h^2} = \sqrt{(5.29\text{ m/s})^2+(5.82\text{ m/s})^2} = 7.9 \text{ m/s}$

4 0

4 years ago

Identify the person who made the correct statement.

dmitriy555 [2]

The answer is: [C]: Neither Juan nor Christina are correct.
_________________________________________________
Explanation:
_____________
Consider Juan's statement:
_______________________
"Juan said fossils deposits always contain only one type of organism."
__________________________
This statement is incorrect. There are many instances of fossil deposits containing more than one type of organism.
___________________________________
Consider Christina's statement.
___________________________________
"Christina said fossil deposits never contain one type of organism."
___________________________________________
This statement is incorrect. Fossil deposits, by definition (of "fossil") ALWAYS contain at least one type of organism.
___________________________________________
As such, neither Juan nor Christina are correct.
And as such, Answer choice: [C] is the correct answer.
_____________________
Answer choices A, B, and D are ruled out.

7 0

3 years ago

3

Misha Larkins [42]

Hi there!

The maximum deformation of the bumper will occur when the car is temporarily at rest after the collision. We can use the work-energy theorem to solve.

Initially, we only have kinetic energy:

$KE = \frac{1}{2}mv^2$

KE = Kinetic Energy (J)
m = mass (1060 kg)
v = velocity (14.6 m/s)

Once the car is at rest and the bumper is deformed to the maximum, we only have spring-potential energy:

$U_s = \frac{1}{2}kx^2$

k = Spring Constant (1.14 × 10⁷ N/m)

x = compressed distance of bumper (? m)

Since energy is conserved:

$E_I = E_f\\\\KE = U_s\\\\\frac{1}{2}mv^2 = \frac{1}{2}kx^2$

We can simplify and solve for 'x'.

$mv^2 = kx^2\\\\x = \sqrt{\frac{mv^2}{k}}$

Plug in the givens and solve.

$x = \sqrt{\frac{(1060)(14.6^2)}{(1.14*10^7)}} = \boxed{0.0198 m}$

3 0

2 years ago

Question 20 of 31

lbvjy [14]

Answer:

C: Valence electrons are transferred from a metal to a nonmetal

Explanation:

In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.

hope this was helpful :)

5 0

3 years ago

SELECT ALL THAT APPLY!! Which of the following are considered SIGNS that a chemical reaction occurred?

MAXImum [283]

Answer:

Formation of a Precipitate

Unexpected Color Change

Formation of a Gas

Explanation:

8 0

3 years ago