Arock is thrown upward with a velocity of 18 meters per second from the top of a 38 meter high cliff, and it misses the cliff on the way back down. when will the rock be 12 meters from the water, below? round your answer to two decimal places.

The rock would be at a point 12 m from water at a time 4.8 s.

Take the origin of the coordinate system at the top of the cliff. It is thrown upwards with a velocity u. When the rock is at a point 12 m from water, calculate the vertical displacement of the rock from the origin.

Use the equation of motion,

The rock falls under the acceleration due to gravity, directed down wards.

Substitute 18 m/s for u, -26 m for y and -9.8 m/s² for a=g.

Solve the quadratic equation for t.

Taking only the positive value,

After a time of 4.8 s the rock would be at a distance of 12 m from water.

The proper and correct arrangement of events in the mantle convection process are:

1. The decomposition of radioactive elements causes heat in the interior part of  the Earth.

2. Heat moves to the core

3. Heat slowly rises to the mantle and creates convection current.

4. Lithospheric plates move in the asthenosphere due to rising and sinking of  materials.

5. The process repeats as a cycle.

Convection is considered to be one of the most efficient ways through which heat is transported from the interior of planet Earth to the surface.

Mantle convection can be defined as the very slow transfer of heat due to the movement of Earth's solid silicate material within the mantle.

Basically, the slow creeping of the mantle causes a transfer of heat from the white-hot core to the brittle lithosphere during mantle convection.

Furthermore, the heating of the mantle takes place from below (the core) and it rises upward in hotter regions while it sinks down in colder regions.

The proper and correct arrangement of events in the mantle convection process are:

1. Heat is caused in the interior part of  the Earth due to the decomposition or decay of radioactive elements.

2. Heat moves to the core.

3. Heat slowly rises from the Earth's core to the mantle and creates convection current in the asthenosphere, which is the plastic layer of the mantle.

4. Lithospheric plates move in the asthenosphere due to rising and sinking of  materials.

5. The process is then repeated as a cycle.

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