Answer:
17.15 m/s
Explanation:
Parameters given:
Magnetic field, B = 0.8 T
Mass of ball, m = 0.007 kg
Charge of ball, q = 0.005 C
The magnetic force acting on the charged ball due to the magnetic field is given as:
F = qvBsinθ
where v = velocity of the ball and θ = angle between the horizontal and the magnetic field = 90°
The force of the ball will be in the opposite direction but of equal magnitude:
= -qvBsin(90) = -qvB
To cancel out the effect of gravity, the magnetic force must be equal to the gravitational force acting on the ball:
F = mg
Therefore:
mg = -qvB
Solving for velocity, v, we have:
v = 17.15 m/s
The ball must be moving at a velocity of 17.15 m/s.
The mass of the child in this problem is 24 Kg, the unit for mass is in Kilogram.
The mass will change only if it travels close to the speed of light.
Answer:both diagrams are attached.
Explanation:
Answer:
b. Friction decreased when he went from pavement to ice and then increased two more times.
Explanation:
Frictional force depends on the normal force of the surface and a friction coefficient.
Since we're talking about the same car, the value of 
will remain constant whereas μ will represent the change in the frictional coefficient of the surface. Now we consider the different surfaces, cars will slide in an icy road which means that the frictional coefficient is smaller than the pavement.
After Joshua returns to the pavement road, the resulting frictional force increases and will do so one more time when he reaches the gravel road. Gravel roads have greater frictional coefficients than pavement roads which means the frictional force will increase a second time.
Answer:
The time constant is 
Explanation:
From the question we are told that
the time take to charge is 
The mathematically representation for voltage potential of a capacitor at different time is
Where 
is the time constant
is the potential of the capacitor when it is full
So the capacitor potential will be 100% when it is full thus 
100% = 1
and from the question we are told that the at the given time the potential of the capacitor is 85% = 0.85 of its final potential so
V = 0.85
Hence
