Question

Recall that the height  at the time  of a rock tossed into the air at time  from a height  at an initial velocity  is given by

Time is measured in seconds, height in feet, and velocity in feet per second. The positive direction is up, so if the rock is moving down then its velocity is negative. The magic number 16 in this equation is due to the mass and radius of earth and would be different for example on Mars or on the Moon. The velocity of the rock at time  is given by

Suppose you throw a rock upward from a height of 64 feet with an initial velocity of 48 feet per second. The rock will hit the ground after seconds.

Answer 1

that As we know accederation due to gravity downward 32.17 40 fill see? initial velocity u feet/ second. h Now, cover When it chil the the ground it- the total elistance 64) feed (2xh46 Now, height when it reaches est maximum velocity of rock is zero. V T 4-gti 48-32t 1.5 second. peale lovint to time taken equal to tą. t. 3 Forum ground

(h+64) utz + Ź gta £ x 3 exta ht 64- But AB 48xt, 48 x 1.5 Ź x3ext, max 1.5*1.5 16 64 36 28 feel ht 64 16 ta 28+ 64 16 ta t. ge 23 5.75 seen ta 55.75 2 Now totex time taken by sock to ground reach the tt ta 1.5tr5175 3.8 g 7 g 3.9 TX 4 second