Answer:-81.29 J
Explanation:
Given
mass of ball
Length of string
height of Room
Gravitational Potential Energy is given by
where h=distance between datum and object
here Reference is ceiling
therefore
Potential Energy of ball w.r.t ceiling
i.e. 81.29 J of Energy is required to lift a ball of mass 2.35 kg to the ceiling
Answer:
V = 1060.8 cm³
Explanation:
we know that the pressure,
P = density x gravity x depth
ρm is the density of mercury
ρw is the density of water
the pressure due to mercury P₁= (ρm) g h₁
the pressure due to water P₂ = (ρw) g h₂
the total pressure
P = P₁ + P₂
P = (ρm) g h₁ + (ρw) g h₂
but the total pressure is double the pressure due to mercury.
(ρm) g h₁ =(ρw) g h₂
h₂ = 81.6 cm
the height of the water is 81.6 cm
the volume
V = height x area
V = 81.6 x 13
V = 1060.8 cm³
the volume of water must be added to double the gauge pressure is V = 1060.8 cm³
Answer:
may experience a magnetic force, but its speed will not change.
Explanation:
A charged particle moving in a static uniform magnetic field experiences a magnetic force (called Lorentz force) which is given by:
where
q is the charge
v is the speed of the particle
B is the magnetic field intensity
is the angle between the direction of the motion of the charge and the direction of the magnetic field
We can notice that when (so, when the particle is moving parallel to the field), the magnetic force is zero, so the particle does not experience any force. This means that we can immediately exclude the following choice:
- will always experience a magnetic force, regardless of its direction of motion.
Moreover, the magnetic force acts perpendicular to the direction of motion of the particle. This means it will change the direction of motion of the particle, so we can also exclude the following option
- may experience a magnetic force, but its direction of motion will not change.
Finally, the fact that the magnetic force is perpendicular to the direction of motion of the particle also implies that the force does no work on the particle. According to the work-energy theorem (which states that the kinetic energy gained by the particle is equal to the work done on it), this implies that the particle gains no kinetic energy, so its speed does not change. This allows us to exclude also the following choice
- a magnetic force which will cause its speed to change.
Therefore, the correct option is the only one remained:
- may experience a magnetic force, but its speed will not change.