1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
soldier1979 [14.2K]
3 years ago
14

An object is dropped from a​ tower, 400 ft above the ground. The​ object's height above ground t seconds after the fall is ​s(t)

equals400 minus 16 t squared. Determine the velocity and acceleration of the object the moment it reaches the ground. The velocity of the object the moment it reaches the ground is nothing ​ft/s.
Physics
1 answer:
Paul [167]3 years ago
7 0

Answer: v= 160ft/s

a=32ft/s^2 constant

Explanation:

s(t)=400-16t^2 derivative of position is velocity v(t) and derivative of velocity is acceleration a(t) so let s(t)=0 to find the time of flight to reach the ground and take the two derivatives and use the time found and solve. Also acceleration is a constant as it’s gravity.

0=400-16t^2

400=16t^2

25=t^2

t=5s

ds/dt=v(t)=0-32t

dv/dt=a(t)=-32 constant(gravity)

v(t)=-32(5s)= -160ft/s negative sign is only showing direction

You might be interested in
Which would likely demagnetize a magnetized iron nail?
Delicious77 [7]
Dropping it on a hard surface. 
5 0
3 years ago
Read 2 more answers
Tritium and helium-3 have the same number of nucleons, but tritium has one proton and two neutrons whereas helium-3 has two prot
ryzh [129]

Answer:

Tritium is more stable.

This happens in part because the tritium nucleus has an extra neutron enhancing the nuclear forces.

Explanation:

The binding energy is the energy that holds nucleons together in the nucleus. It depends on the number of nucleons present in the nucleus. The greater the number of nucleons, the greater the binding energy.

Also, the more the number of neutrons in a nucleus, the greater the nuclear forces. Helium-3 has only one neutron while tritium has two neutrons. The extra neutron in tritium enhances the nuclear forces hence tritium has a greater binding energy than Helium-3

6 0
3 years ago
According to a newspaper account, a paratrooper survived a training jump from 1200 ft when his parachute failed to open but prov
Schach [20]
<span>Let's make a few assumptions. 1. The paratrooper's lowest speed will be just prior to impact. 2. Since the jump was from a relatively low altitude, the paratrooper used a static line and the parachute should have opened almost immediately upon jumping. So let's convert 100 mi/h to ft/s 100 mi/h * 5280 ft/mi / 3600 s/h = 146.67 ft/sec Given the 1st assumption above, the MAXIMUM distance the paratrooper would have fallen would be 8 seconds at 146.67 ft/s, so 8 s * 146.67 ft/s = 1173.36 ft The calculated distance is close to the jump distance, which agrees with both assumptions 1 and 2. So this account does seem reasonable. Additionally, looking for the speed of a parachutist doing a freefall in the belly-to-earth position with arms and legs outspread, they will generally reach a terminal velocity of 120 mi/h which is slightly faster than the 100 mi/h in the article. This too is in agreement with the defective parachute flapping and causing some extra air resistance.</span>
7 0
3 years ago
How is refraction and reflection different?
ss7ja [257]

Answer:

Refraction are in parts or are reflected brokely, like light against aluminum. While a reflection, is exact. Like a mirror.

7 0
3 years ago
Read 2 more answers
If you drop a rock off a cliff and it hits the ground 3 seconds later how tall is that cliff
skelet666 [1.2K]

Answer:

Basic kinematics, negating drag and assuming ideal conditions, we use the equation:

d=vi*t+1/2*a*t^2

Since vi is 0 (we know this because you’re dropping it, not throwing it)…

…and the only acceleration acting on it is gravity, a=9.8 m/s^2…

…we get

d=1/2(9.8)(5)^2

Explanation:

Some quick mental math tells us that this is about 125 m.

Plugging it in, we find it to be 122.5 m.

6 0
3 years ago
Other questions:
  • How many cubic feet are there in a gallon?
    8·2 answers
  • Which of these mixtures would be easiest to separate?
    14·1 answer
  • You discover an asteroid that orbits the Sun with the same 1-year orbital period as Earth. Which of the following statements mus
    9·1 answer
  • Determine the value of a for which the maximum positive moment has the same magnitude as the maximum negative moment. ei is cons
    13·1 answer
  • A bicyclist, traveling with a constant speed, covers 61.Om in 7.80s.
    9·1 answer
  • What goes on the vertical (Y) axis
    10·1 answer
  • 1)Light of wavelength 588.0 nm is incident on a narrow slit. The diffraction pattern is viewed on a screen 55.5 cm from the slit
    13·1 answer
  • Describe what happens to the particles of water when it boils.
    12·1 answer
  • Kyle, a 85.0 kg football player, leaps straight up into the air (with no horizontal velocity) to catch a pass. He catches the 0.
    12·1 answer
  • Hi people see bye 18 45 36
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!