Moment of a Force - I Love Physics Forever!
... support. A weight of 1.20 N is hanged 5 cm from the left end. It was found out that an unknown weight W would balance the plank if it is positioned 72 cm from the left end. What is the weight W of the object? How much force is exerted by the support on the plank? ...
... support. A weight of 1.20 N is hanged 5 cm from the left end. It was found out that an unknown weight W would balance the plank if it is positioned 72 cm from the left end. What is the weight W of the object? How much force is exerted by the support on the plank? ...
Forces - pushes or pulls Contact forces
... 67° north of east. Ignoring water resistance, find the x and y components of the raft’s acceleration. ...
... 67° north of east. Ignoring water resistance, find the x and y components of the raft’s acceleration. ...
Chapter 2 - Test Bank 1
... 53. Since it starts going up at 40 m/s and loses 10 m/s each second, its time going up is 4 seconds. Its time returning is also 4 seconds, so it’s in the air for a total of 8 seconds. Distance up (or down) is 1/2 gt2 = 5 42 = 80 m. Or from d = vt, where average velocity is (40 + 0)/2 = 20 m/s, and ...
... 53. Since it starts going up at 40 m/s and loses 10 m/s each second, its time going up is 4 seconds. Its time returning is also 4 seconds, so it’s in the air for a total of 8 seconds. Distance up (or down) is 1/2 gt2 = 5 42 = 80 m. Or from d = vt, where average velocity is (40 + 0)/2 = 20 m/s, and ...
Weightlessness
Weightlessness, or an absence of 'weight', is an absence of stress and strain resulting from externally applied mechanical contact-forces, typically normal forces from floors, seats, beds, scales, and the like. Counterintuitively, a uniform gravitational field does not by itself cause stress or strain, and a body in free fall in such an environment experiences no g-force acceleration and feels weightless. This is also termed ""zero-g"" where the term is more correctly understood as meaning ""zero g-force.""When bodies are acted upon by non-gravitational forces, as in a centrifuge, a rotating space station, or within a space ship with rockets firing, a sensation of weight is produced, as the contact forces from the moving structure act to overcome the body's inertia. In such cases, a sensation of weight, in the sense of a state of stress can occur, even if the gravitational field was zero. In such cases, g-forces are felt, and bodies are not weightless.When the gravitational field is non-uniform, a body in free fall suffers tidal effects and is not stress-free. Near a black hole, such tidal effects can be very strong. In the case of the Earth, the effects are minor, especially on objects of relatively small dimension (such as the human body or a spacecraft) and the overall sensation of weightlessness in these cases is preserved. This condition is known as microgravity and it prevails in orbiting spacecraft.