Answer: It takes 2.85 seconds.
Explanation: according to the question, the kinematics equation for vertical motion is
y₀ is the initial postion and equals 0 because it is fired at ground level;
v₀ is the initial speed and eqauls 14m/s;
g is gravity and it is 9.8m/s²;
y(t) is the final position and equals 0 because it is when the pumpkin hits the ground;
Rewriting the equation, we have:
0 + 14t - 
= 0
14t - 4.9t² = 0
t(14 - 4.9t) = 0
For this equation to be zero,
t = 0 or
14 - 4.9t = 0
- 4.9t = - 14
t = 
t = 2.86
It takes 2.86 seconds for the pumpkin to hit the ground.
Answer:
The total mechanical energy of a pendulum is conserved neglecting the friction.
Explanation:
- When a simple pendulum swings back and forth, it has some energy associated with its motion.
- The total energy of a simple pendulum in harmonic motion at any instant of time is equal to the sum of the potential and kinetic energy.
- The potential energy of the simple pendulum is given by P.E = mgh
- The kinetic energy of the simple pendulum is given by, K.E = 1/2mv²
- When the pendulum swings to one end, its velocity equals zero temporarily where the potential energy becomes maximum.
- When the pendulum reaches the vertical line, its velocity and kinetic energy become maximum.
- Hence, the total mechanical energy of a pendulum as it swings back and forth is conserved neglecting the resistance.
75
p = w / t
p = 180 / 2.4
p = 75
Trust vs Mistrust
At this stage the infant is uncertain about the world they live in.
Answer:
<em>mass</em>
<em></em>
Explanation:
Density is the measure of how much mass of a substance is squeezed into a given volume of that substance. <em>It is the mass per unit volume</em>, and substances with lesser density will float in materials with denser density. Buildings are generally more obviously denser that air, if not we'll see then float upwards into the atmosphere, but that is not the case. Different liquids too can separate and form layers on one another due to their differences in volume.
