Answer:
A.Gravity acts to pull the object down
D.The object’s inertia carries it forward.
E.The path of the object is curved.
Explanation:
The motion of a projectile consists of two independent motions:
- A uniform motion along the horizontal direction, with constant horizontal speed
- A vertical motion with constant acceleration of g = 9.8 m/s^2 downward (acceleration due to gravity), due to the presence of the force of gravity, so the vertical velocity changes (increases in the downward direction)
As a result, the combined motion of the projectile has a curved trajectory (parabolic, more specifically). So the following options are correct:
A.Gravity acts to pull the object down --> gravity acts along the vertical direction
D.The object’s inertia carries it forward. --> there are no forces acting along the horizontal direction (if we neglect air resistance), so the horizontal motion continues with constant speed
E.The path of the object is curved
Answer:
Primary waves (P-waves)
Explanation:
Due to excess of the energy inside the earth when the tectonic plates begin to slide or fracture then the energy is released in the form of seismic waves, this causes the earthquake.
<u>Two types of seismic waves are generally responsible for the earth quakes:</u>
- body waves
- surface waves
Body waves are of two types:
Primary waves (P-waves)
These are the fastest of all the waves involved in the earth-quake which travel at a speed of 1.6 km to 8 km per second.
They can pass trough solids, liquids and gases. They arrive at the surface as an instant thud.
Secondary waves (S-waves)
They can only pass through the solids and they move slower than the P-waves.
As S-waves move, they displace the rock particles, pushing them outwards perpendicular to the wave-path that leads to the earthquake-related first rolling period.
Surface waves (L-waves/ long waves)
- These waves move along the surface of the earth. They are responsible for the earthquake's carnage.
- They move up and down the Earth's surface, rocking the foundations of man-made structures.
- Surface waves are slowest of the three waves, which means that they are the last to arrive. So at the end of an earthquake usually comes the most powerful shaking.
Answer:
The gravity on this planet is stronger than that of earth.
Explanation:
First we need to find the acceleration due to gravity value of this planet to compare its gravity force with that of the earth. Hence, we will use second equation of motion:
h = Vi t + (0.5)gt²
where,
h = height or depth of crater = 100 m
Vi = Initial Velocity of rock = 0 m/s
t = time = 4 s
g = acceleration due to gravity on this planet = ?
Therefore,
100 m = (0 m/s)(4 s) + (0.5)(g)(4 s)²
g = (200 m)/(16 s²)
g = 12.5 m/s²
on earth:
ge = 9.8 m/s²
Since,
ge < g
Therefore,
<u>The gravity on this planet is stronger than that of earth.</u>
Answer:
False
Explanation:
Most comets are located outside the solar system, in part of the cloud that originated from dust and gas that has remained virtually untouchable for billions of years. The orbit of these comets can reach the order of a light year. Thus, they are called long-period comets.
