Explanation:
Assuming the wall is frictionless, there are four forces acting on the ladder.
Weight pulling down at the center of the ladder (mg).
Reaction force pushing to the left at the wall (Rw).
Reaction force pushing up at the foot of the ladder (Rf).
Friction force pushing to the right at the foot of the ladder (Ff).
(a) Calculate the reaction force at the wall.
Take the sum of the moments about the foot of the ladder.
∑τ = Iα
Rw (3.0 sin 60°) − mg (1.5 cos 60°) = 0
Rw (3.0 sin 60°) = mg (1.5 cos 60°)
Rw = mg / (2 tan 60°)
Rw = (10 kg) (9.8 m/s²) / (2√3)
Rw = 28 N
(b) State the friction at the foot of the ladder.
Take the sum of the forces in the x direction.
∑F = ma
Ff − Rw = 0
Ff = Rw
Ff = 28 N
(c) State the reaction at the foot of the ladder.
Take the sum of the forces in the y direction.
∑F = ma
Rf − mg = 0
Rf = mg
Rf = 98 N
So the answer is B. because the mass have Kg as a international unit and velocity is m/s, they are international units in physics.
Answer:
Infrasound
but the longer the wavelength of a soundwave, the more it diffracts
Explanation:
Answer:About 860,000 results (1.08 seconds)
kettle-power
Jun 18, 2014 — It's interesting to see how much energy heating and cooling systems use ... the kettle uses goes into the water it costs more to use electricity to boil ... 3 minutes is 1/20 of an hour, so 2.4kW for 3 minutes is equivalent to 2.4 / 20 = 0.12kWh. ... kettle should NOT clock over 1kw/h in the 4 minutes it takes to boil
Explanation:
Answer:
15
Explanation:
atomic no. = no. of protons
