1) The grapefruit is in free fall, so it moves by uniformly accelerated motion, with constant acceleration

. Calling h its height at t=0, the height at time t is given by

We are told thatn when

the grapefruit hits the ground, so h(0.75 s)=0. If we substitute these data into the equation, we can find the initial height h of the grapefruit:


2) The speed of the grapefruit at time t is given by

where

is the initial speed of the grapefruit. Substituting t=0.75 s, we find the speed when the grapefruit hits the ground:
Answer:
222.2N/m
Explanation:
Given parameters:
Elastic potential energy = 4000J
Extension = 6m
Unknown:
Spring coefficient = ?
Solution:
The elastic potential energy is the energy stored within a string.
It is expressed as;
EPE =
k e²
k is the spring constant
e is the extension
4000 =
x k x 6²
8000 = 36k
k = 222.2N/m
Answer:
Diameter of Wire = 4.5 mm
Explanation:
First, we need to find the fractional part of the reading. The fractional part o the reading can be given by the following formula:
Fractional Part = Circular Scale Reading x Least Count
where,
Circular Scale Reading = 50
Least Count = 0.01 mm
Therefore,
Fractional Part = (50)(0.01 mm)
Fractional Part = 0.5 mm
Now, the diameter of the wire can be given by using the following formula:
Diameter of Wire = Linear Scale Reading + Fractional Part
Diameter of Wire = 4 mm + 0.5 mm
<u>Diameter of Wire = 4.5 mm</u>
Answer: A Hydrothermal vent
Explanation: