# An object is thrown vertically from a height of #7# #m# at # 4# #ms^-1#. How long will it take for the object to hit the ground?

##### 1 Answer

#### Answer:

**Assuming the object has initial upward velocity**

**Assuming the object has initial downward velocity**

#### Explanation:

We have been given the following informations

The object is thrown *with velocity

from a height of

**Assuming the object has initial upward velocity**

#u =+4# #ms^-1-> "upward taken +ve"# #h= -7# #m ->"downward taken -ve"# - Acceleration due to gravity
#g=-9.8# #ms^-2 ->"downward taken -ve"#

So the equation,

**Assuming the object has initial downward velocity**

#u =+3# #ms^-1-> "downward taken +ve"# #h= +7# #m ->"downward taken +ve"# - Acceleration due to gravity
#g=+9.8m/s^2 ->"downward taken +ve"#

So the equation,