Engineering
Here's how to build a whirligig: Thread a loop of twine through two holes in a button. Grab the loop ends, then rhythmically pull. As the twine coils and uncoils, the button spins at a dizzying speed.
Jan 10, 2017
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1905
Energy & Green Tech
Scientists from the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have discovered a possible secret to dramatically boosting the efficiency of perovskite solar cells hidden in the nanoscale peaks ...
Jul 4, 2016
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32
Hi Tech & Innovation
A team of researchers working at Stanford University has used prior research involving the means by which gecko's climb walls to create pads that allow a human to do very nearly the same thing. In their paper published in ...
Robotics
The findings of new biomechanics research could be used to develop more effective rehabilitation techniques for patients with musculoskeletal injuries.
Oct 10, 2023
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16
Robotics
Running on the beach versus a paved road can change an athlete's stride, speed and stability. Alter the force of gravity, and that runner may break their personal record or sink into the ground. Researchers have to consider ...
Sep 26, 2023
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46
Energy & Green Tech
A team of mechanical engineers at Beihang University, Peking University and the University of Houston has found that it is possible to capture small amounts of electricity by repeatedly squeezing treated luffa sponges. In ...
Energy & Green Tech
There is a largely untapped energy source along the world's coastlines: the difference in salinity between seawater and freshwater. A new nanodevice can harness this difference to generate power.
Sep 24, 2023
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407
Robotics
Soft inflatable robots have emerged as a promising paradigm for applications that require inherent safety and adaptability. However, the integration of sensing and control systems in these robots has posed significant challenges ...
Sep 15, 2023
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21
Robotics
This robot can swim under the sand and dig itself out too, thanks to two front limbs that mimic the oversized flippers of turtle hatchlings.
Jul 18, 2023
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68
Electronics & Semiconductors
Researchers have developed next-generation smart textiles—incorporating LEDs, sensors, energy harvesting, and storage—that can be produced inexpensively, in any shape or size, using the same machines used to make the ...
Apr 21, 2023
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134
In physics, a force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. In other words, a force is that which can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate, or which can cause a flexible object to deform. Force can also be described by intuitive concepts such as a push or pull. A force has both magnitude and direction, making it a vector quantity. Newton's second law, F=ma, was originally formulated in slightly different, but equivalent terms: the original version states that the net force acting upon an object is equal to the rate at which its momentum changes.
Related concepts to force include: thrust, which increases the velocity of an object; drag, which decreases the velocity of an object; and torque which produces changes in rotational speed of an object. Forces which do not act uniformly on all parts of a body will also cause mechanical stresses, a technical term for influences which cause deformation of matter. While mechanical stress can remain embedded in a solid object, gradually deforming it, mechanical stress in a fluid determines changes in its pressure and volume.
This text uses material from Wikipedia, licensed under CC BY-SA
