Answer:
ms⁻¹
Explanation:
Consider the motion of the bullet-block combination after collision
= mass of the bullet = 0.0382 kg
= mass of wooden block = 3.78 kg
= velocity of the bullet-block combination after collision
= spring constant of the spring = 833 N m⁻¹
= Amplitude of oscillation = 0.190 m
Using conservation of energy
Kinetic energy of bullet-block combination after collision = Spring potential energy gained due to compression of spring


ms⁻¹
= initial velocity of the bullet before striking the block
Using conservation of momentum for the collision between bullet and block


ms⁻¹
The answer is:
71.6 <span>°F</span>
The movement of the tectonic plates is caused by convection currents in Earth´s mantle.
Answer: A) convection currents in Earth´s mantle.
<h2>
Option A is the correct answer.</h2>
Explanation:
Acceleration due to gravity

G = 6.67 × 10⁻¹¹ m² kg⁻¹ s⁻²
Let mass of earth be M and radius of earth be r.
We have

Now
A hypothetical planet has a mass of one-half that of the earth and a radius of twice that of the earth.
Mass of hypothetical planet, M' = M/2
Radius of hypothetical planet, r' = 2r
Substituting

Option A is the correct answer.
To solve this problem we will apply the concepts related to the Doppler effect. According to this concept, it is understood as the increase or decrease of the frequency of a sound wave when the source that produces it and the person who captures it move away from each other or approach each other. Mathematically this can be described as

Here,
= Original frequency
= Velocity of the observer
= Velocity of the speed
Our values are,



Using the previous equation,

Rearrange to find the velocity of the observer

Replacing we have that


Therefore the velocity of the observer is 16.2m/s