Answer:
The mass of the child + skateboard is 50 kg
Explanation:
In this problem, we can apply Newton's second law:
F = ma
where
F is the net force on a system
m is the mass of the system
a is the acceleration of the system
In this problem, our system is the child + the skateboard. The net force on them is
F = 75 N
and their acceleration is
So we can re-arrange the equation above to find their combined mass:
Gravitational potential energy i think
The lights are wired in PARALLEL.
In fact, when the lights are connected in parallel, they are connected on separate branches to the source of voltage, so if one light bulb burns out, the other lights continue to work because the current continues to flow in the other branches of the circuit.
Vice-versa, if the light bulbs are connected in series, they are on the same branch This means that if one of them burns out, the circuit is open in that point, so the current cannot flow anymore and the other light bulbs turn off as well.
Answer:
Explanation:
a ) The earth rotates by 2π radian in 24 x 60 x 60 s
so angular speed ( w ) = 2π / (24 x 60 x 60) = 7.268 x 10⁻⁵ rad / s
b ) Linear speed of city of Arlington ( v ) = w r = w R Cosλ where R is radius of the earth and λ is latitude .
v = 7.268 x 10⁻⁵ x 6.371 x 10⁶ cos 32.7357
389.5 m /s
acceleration = w² r = w² R Cos 32.7357
= (7.268 x 10⁻⁵ )² x 6.371 x 10⁶ x cos 32.7357
=283.08 x 10⁻⁴ m/s²
c) velocity ratio =
w r /w R =
R cos 32.73/ R
= Cos 32.73
= 0.84 .
