but tpla ybut tpla y but tpl but tpla y but tpla y but tpla ya y but tpla y but tpla y
Explanation:
In physics, work is the energy transferred to or from an object via the application of force along a displacement. In its simplest form, it is often represented as the product of force and displacement. A force is said to do positive work if (when applied) it has a component in the direction of the displacement of the point of application. A force does negative work if it has a component opposite to the direction of the displacement at the point of application of the force.
Quick Facts: Common symbols, SI unit ...
Work
A baseball pitcher does positive work on the ball by applying a force to it over the distance it moves while in his grip.
Common symbols
W
SI unit
joule (J)
Other units
Foot-pound, Erg
In SI base units
1 kg⋅m2⋅s−2
Derivations from
other quantities
W = F ⋅ s
W = τ θ
Dimension
M L2 T−2
Close
For example, when a ball is held above the ground and then dropped, the work done by the gravitational force on the ball as it falls is equal to the weight of the ball (a force) multiplied by the distance to the ground (a displacement). When the force F is constant and the angle between the force and the displacement s is θ, then the work done is given by:
{\displaystyle W=Fs\cos {\theta }}{\displaystyle W=Fs\cos {\theta }}
Work is a scalar quantity, so it has only magnitude and no direction. Work transfers energy from one place to another, or one form to another. The SI unit of work is the joule (J), the same unit as for energy.
Answer:
B. 2. A baseball was hit by a bat and now flying through the air.
Explanation: A baseball that is hit by a bat has a larger velocity, due to this the amount of kinetic energy is high.
Answer:
at d the charge will be 3q and at 3d it will be 9q
Explanation:
for V=Vp-V2d
V=KQ/d=K*6q/2d=3kq/d for potential to 2d at 6q be zero the Vp will equal 3kq/d; hence at d, Q=3q and at 3d, Q=9q
Answer:
E. greater than the angle of incidence.
Explanation:
Snell's law states that:
(1)
where
are the refractive index of the first and second medium
are the angle of incidence and refraction, respectively
For light moving from water to air, we have:
(index of refraction of water)
(index of refraction of air)
Substituting into (1) and re-arranging the equation, we get
which means that
so, the correct answer is
E. greater than the angle of incidence.
