Answer:
After 9 seconds the object reaches ground.
Step-by-step explanation:
We equation of motion given as h = -16t²+128t+144,
We need to find in how many seconds will the object hit the ground,
That is we need to find time when h = 0
0 = -16t²+128t+144
16t²-128t-144= 0
Negative time is not possible, hence after 9 seconds the object reaches ground.
Please provide the choices to select the possible choices.
Answer:
1. 0.45 s.
2. 4.41 m/s
Explanation:
From the question given above, the following data were obtained:
Height (h) = 1 m
Time (t) =?
Velocity (v) =?
1. Determination of the time taken for the pencil to hit the floor.
Height (h) = 1 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =?
h = ½gt²
1 = ½ × 9.8 × t²
1 = 4.9 × t²
Divide both side by 4.8
t² = 1/4.9
Take the square root of both side
t = √(1/4.9)
t = 0.45 s.
Thus, it will take 0.45 s for the pencil to hit the floor.
2. Determination of the velocity with which the pencil hit the floor.
Initial velocity (u) = 0 m/s
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) = 0.45 s.
Final velocity (v) =?
v = u + gt
v = 0 + (9.8 × 0.45)
v = 0 + 4.41
v = 4.41 m/s
Thus, the pencil hit the floor with a velocity of 4.41 m/s
Sum of all forces = mass * acceleration
Ft= tension force
Fw= force of gravity (Fw= mass* acceleration of gravity which is 9.8 this only applies to force of gravity)
Ft- Fw = 0 (there is no acceleration)
Ft = Fw
Ft= m*g
Ft= 0.250kg*9.8m/s
Ft= 2.45N
Well, the rings surrounding a planet are made out of rock. A ring surrounding the sun would be impossible since the sun can reach more than 27 million degrees Fahrenheit (15 million degrees Celsius.)
Hope this helped.
