Answer:
Negative acceleration occurs when the acceleration vector points to the left.
1. Object slowing down in the positive direction.
2. Object speeding up in the negative direction.
Following six statements:
1. T
2. F
3. T
4. T
5. F
6. T
Check direction of acceleration vector.
I have two (2) brilliant ideas:
1). Inside the metal that the body of the car is made of, and also between the two sheets of glass that the windows are made of, install a thin layer of material that absorbs RF (radio-wave) energy . . . like the material in the glass window of your microwave oven. Then, no radio waves from the cellular base station can get INTO the car, and no radio waves from your phone can get OUT of the car. The phone can't make a connection to the cellular network, you can't make or receive calls, and you can't connect to Instagram or Brainly, so you might as well just turn it off and save your battery until next time you're outside your car.
2). Somewhere inside the car, like under the dash or in the glove box, install a teeny tiny radio receiver that can recognize the signals coming OUT of your phone. Connect it to the car's electrical system so that when it hears signals from phones inside the car, it it shuts down the car's motor so you can't start or drive. The car only works when phones inside the car are either turned off or in Airplane Mode.
My ideas are so brilliant that I really should patent them, or copyright them, or whatever you do so that other people have to pay you to use your idea. But if you want to use them, that's OK. Just go ahead. I won't mind.
Answer:
The minimum compression is 
Explanation:
From the question we are told that
The mass of the block is 
The spring constant is 
The coefficient of static friction is 
For the the block not slip it mean the sum of forces acting on the horizontal axis is equal to the forces acting on the vertical axis
Now the force acting on the vertical axis is the force due to gravity which is mathematically given as
And the force acting on the horizontal axis is force due to the spring which is mathematically represented as
where x is the minimum compression to keep the block from slipping
Now equating this two formulas and making x the subject
substituting values we have
Explanation:
Load (l) = 680N
Effort (E) = 500N
Length slope (l) = 12m
Height slope (h) = 8 m
Output = load * height
680 *8 = 5.44 *103 J
The Input = effort * length = 500 *12 = 6000J
the Mechanical advantage (M.A) = load effort= 600500=1.36
the Velocity ratio (V.R) =lh=128 = 1.5
the Efficiency =M.A100%V.R= 90.6%
