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
hjlf
3 years ago
5

An object is falling from a height of 7.5 meters. At what height will its velocity be 7 meters/second?

Physics
1 answer:
Ivanshal [37]3 years ago
8 0

Answer:

5.0 m

Explanation:

The velocity of the object at time t is given by

v=at

where a=9.8 m/s^2 is the acceleration of gravity and t is the time. If we substitute v=7 m/s, we can find the time t at which the velocity became 7 m/s:

t=\frac{v}{a}=\frac{7 m/s}{9.8 m/s^2}=0.71 s

The height of the object at time t, h(t), is given by the equation

h(t)=h_0 -\frac{1}{2}at^2

where h_0 = 7.5 m is the initial height. By substituting t=0.71 s inside the equation, we find the height h(t) at which the velocity is 7 m/s:

h(0.71 s)=7.5 m- \frac{1}{2}(9.8 m/s^2)(0.71 s)^2=5.0 m

You might be interested in
Please Please Please Can Help Me On This Question!!!!! I Give Thanks!!!! Please Do 1-4!!!!
ololo11 [35]
1.add the amount of the diagram which is M+Y then dived the answer you get.
5 0
3 years ago
Read 2 more answers
A seesaw pivots as shown in below. What is the net torque about the pivot point?
rodikova [14]

Answer:

2.3 Nm clockwise

Explanation:

Take counterclockwise to be positive and clockwise to be negative.

∑τ = (3 N) (2.5 m) − (7 N) (1.4 m)

∑τ = 7.5 Nm − 9.8 Nm

∑τ = -2.3 Nm

The net torque is 2.3 Nm clockwise.

7 0
3 years ago
Use your knowledge of waves to explain why echoes occur. Use your explanation to devise a system to measure distances to objects
german

Explanation:

Echoes occur due to the reflection of sound from any obstacle, but not all the reflected sound waves lead to the phenomenon of echo. For the echo to be heard it actually depends upon the human perception as well, human ears can encounter the difference between the sound wave directly form the source and the reflected sound waves only if there is a minimum time gap of one-tenth of a second. For this time gap in the atmosphere at normal temperature and pressure the obstacle must be at least 7 meters away from the sound source.

3 0
3 years ago
BRAINLIEST FOR YOU IF YOU ANSWER
luda_lava [24]

Answer:

d

Explanation:

i think

5 0
2 years ago
The world speed record on water was set on October
Luda [366]

Answer: Remember speed is distance divided by time, so if he travels 1000 m in 7.045 s, his speed is

(1000 m)/(7.045 s) = 141.9 m/s.

Note there are 1609 metres in a mile, or 1 mi = 1609 m, so m = 1/1609 mi, or

141.9/1609 mi/s = 0.08822 mi/s. Now, note that 1 h = 3600 s, so the speed is

0.08822*3600 mi/h = 317.6 mi/h.

8 0
3 years ago
Other questions:
  • For which pair of launch angles will two identical projectiles have equal ranges?. A. 19.24°, 80.54°B. 16.42°, 74.58°C. 60.23°,
    9·2 answers
  • Which tool do we use to measure wind
    13·2 answers
  • A resistor with resistance R and an air-gap capacitor of capacitance C are connected in series to a battery (whose strength is "
    13·1 answer
  • a ball is thrown horizontally from the roof of a building 45.0 m tall and lands 24.0 m from the base. What was the ball´s initia
    9·1 answer
  • When does the transfer of thermal energy end?​
    9·1 answer
  • When a glass rod is rubbed with silk and becomes positively charged,
    9·1 answer
  • Assume we’re able to travel to your planet and decide to take some fireworks with us to celebrate our journey.
    11·1 answer
  • How did Einstein’s and Newton’s theories differ in terms of explaining the cause of gravity?
    15·2 answers
  • NEED ANSWER ASAP PLEASE!!!!!!!
    10·1 answer
  • according to Newton's __ law, an object with no net force acting on it remains at rest or in motion with a constant veloctiy
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!