Help Solve 6 Online Homework Problems

  • Thread starter idon'tgetphysics
  • Start date
In summary, the conversation is about a student seeking help with 6 online homework problems. They provide the questions, their solutions, and their answers. They are unsure about some of their answers and ask for assistance in finding their mistakes. The problems involve kinematic equations, finding time and angle, and calculating force and tension. The student also mentions using a forum for the first time and provides a hint for one of the problems. They end by expressing gratitude for any help they receive.
  • #1
idon'tgetphysics
1
0
ok, so i have 6 online homework problems that i worked out. i thought that they were all right, but turns out that 2 of them are wrong. i don't know which ones are wrong, and what i did wrong. help please!

i'll write the problems, how i solved, and my answer...i've never used this forum before so I'm not sure if I'm doing this right. appreciate anyone that can help.

Question #1: a football is kicked at ground level with a speed of 17.7 m/s at an angle of 46.0 degrees to the horizontal. how much later does it hit the ground.

Answer #1: t=2.59 seconds, i found this answer by finding the y component of the vector and using a kinematic equation.

Question #2: the pilot of an airplane traveling 1.80E2 km/h wants to drop supplies to flood victims isolated on a patch of land 1.30E2 m below. the supplies should be dropped how many seconds before the plane is directly overhead? (find time in seconds)

Answer #2: t=5.15 seconds, i used the kinematic equation...y=y(initial) + v(initial)*time + 1/2 (a) (t^2)...-130=.5(-9.8)t^2

Question #3: William Tell must split the apple atop his son's head from a distance of 26m. when william aims directly at the apple, the arrow is horizontal. at what angle must he aim it to hit the apple if the arrow travels at a speed of 35m/s? Assume that the arrow is released at the same height as the apple.

Answer #3: 6.0 degrees, i used the equation sin2x= (Rg)/v(initial)^2 ...R is the horizontal range, which is 26m and g is gravity, v(initial) is 35

Question #4: what average force is required to stop an 1.03E3 kg car in 8.60 seconds if the car is traveling at 96.0 km/h?

Answer #4: -3.19E2N...first, i converted 96.0 to m/s (which I'm not sure if I'm supposed to do) then i found the acceleration, then i put that in F=ma

Question #5: How much tension must a rope withstand if it is used to accelerate a 2.3E3 kg car vertically upward at .54m/s^2?

Answer #5: 23782N (which is 2.4E4 with significant figures) i did FofT=ma-mg

Question #6: a person stands on a bathroom scale in a motionless elevator. when the elevator begins to move, the scale briefly reads only 0.77 of the person's regular weight. a) calculate the acceleration of the elevator and b) find the direction of the acceleration...hint (down is negative, up is positive)

Answer #6: -2.3 m/s^2 and the direction is down...i did this by looking at an example in the book...not really sure how to explain it

so...i know this is a lot, but if anyone can tell me what i did wrong, it'll make my week. thanks!
 
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  • #2
Question #4

F=ma
[tex]F=1.03X10^3[\frac{0-\frac{96.0X10^3}{3600}}{8.60}][/tex]
[tex] = -3.19X10^3 N [/tex]

instead of [tex]-3.19X10^2 N[/tex]
 
  • #3
idon'tgetphysics said:
ok, so i have 6 online homework problems that i worked out. i thought that they were all right, but turns out that 2 of them are wrong. i don't know which ones are wrong, and what i did wrong. help please!

i'll write the problems, how i solved, and my answer...i've never used this forum before so I'm not sure if I'm doing this right. appreciate anyone that can help.

Question #1: a football is kicked at ground level with a speed of 17.7 m/s at an angle of 46.0 degrees to the horizontal. how much later does it hit the ground.

Answer #1: t=2.59 seconds, i found this answer by finding the y component of the vector and using a kinematic equation.

Question #2: the pilot of an airplane traveling 1.80E2 km/h wants to drop supplies to flood victims isolated on a patch of land 1.30E2 m below. the supplies should be dropped how many seconds before the plane is directly overhead? (find time in seconds)

Answer #2: t=5.15 seconds, i used the kinematic equation...y=y(initial) + v(initial)*time + 1/2 (a) (t^2)...-130=.5(-9.8)t^2

Question #3: William Tell must split the apple atop his son's head from a distance of 26m. when william aims directly at the apple, the arrow is horizontal. at what angle must he aim it to hit the apple if the arrow travels at a speed of 35m/s? Assume that the arrow is released at the same height as the apple.

Answer #3: 6.0 degrees, i used the equation sin2x= (Rg)/v(initial)^2 ...R is the horizontal range, which is 26m and g is gravity, v(initial) is 35

Question #4: what average force is required to stop an 1.03E3 kg car in 8.60 seconds if the car is traveling at 96.0 km/h?

Answer #4: -3.19E2N...first, i converted 96.0 to m/s (which I'm not sure if I'm supposed to do) then i found the acceleration, then i put that in F=ma

Question #5: How much tension must a rope withstand if it is used to accelerate a 2.3E3 kg car vertically upward at .54m/s^2?

Answer #5: 23782N (which is 2.4E4 with significant figures) i did FofT=ma-mg

Question #6: a person stands on a bathroom scale in a motionless elevator. when the elevator begins to move, the scale briefly reads only 0.77 of the person's regular weight. a) calculate the acceleration of the elevator and b) find the direction of the acceleration...hint (down is negative, up is positive)

Answer #6: -2.3 m/s^2 and the direction is down...i did this by looking at an example in the book...not really sure how to explain it

so...i know this is a lot, but if anyone can tell me what i did wrong, it'll make my week. thanks!

I didn't spot ne mistakes... but maybe some else will
 
  • #4
Question #3

Answer given was not complete.

sin (2x) = 0.2082
[tex]2x = 12.02^0; 180^0-12.02^0[/tex]
[tex]x=6.0^0 or 84^0[/tex]
 

What is "Help Solve 6 Online Homework Problems"?

"Help Solve 6 Online Homework Problems" is a service that provides assistance in solving six online homework problems for students in various subjects, such as math, science, language arts, etc. It is designed to help students understand and complete their homework assignments more efficiently.

How does "Help Solve 6 Online Homework Problems" work?

The process is simple. Students submit their homework problems to the website and a team of knowledgeable experts will work on solving them. The solutions will then be provided to the students, along with explanations and tips for better understanding.

Who are the experts providing the solutions?

The experts are highly qualified individuals with extensive knowledge in their respective fields. They have gone through rigorous testing and training to ensure the accuracy and quality of their solutions. They are also available to answer any questions or provide additional assistance if needed.

Is "Help Solve 6 Online Homework Problems" a cheating service?

No, it is not. The solutions provided are meant to be used as a study aid and reference material for students to better understand the concepts. It is the responsibility of the student to use the solutions ethically and to not submit them as their own work.

Is "Help Solve 6 Online Homework Problems" available for all subjects?

Currently, "Help Solve 6 Online Homework Problems" is available for a wide range of subjects, including math, science, social studies, and language arts. However, if there is a subject that is not currently covered, students can still submit their homework problems and the team will do their best to provide assistance.

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