Answer:
F = 5226.6 N
Explanation:
To solve a lever, the rotational equilibrium relation must be used.
We place the reference system on the fulcrum (pivot point) and assume that the positive direction is counterclockwise
F d₁ = W d₂
where F is the applied force, W is the weight to be lifted, d₁ and d₂ are the distances from the fulcrum.
In this case the length of the lever is L = 5m, t the distance desired by the fulcrum from the weight to be lifted is
d₂ = 200 cm = 2 m
therefore the distance to the applied force is
d₁ = L -d₂
d₁ = 5 -2
d₁= 3m
we clear from the equation
F = W d₂ / d₁
W = m g
F = m g d₂ / d₁
we calculate
F = 800 9.8 2/3
F = 5226.6 N
Answer:
FAE= 0.014 N
Explanation:
The KE of block is decreased because of the slowing action of the friction force .
Change in KE of block = work done on block by friction ƒ
⠀ ➪ ½mu²ƒ - ½mu²i = Fƒs cos θ
Because the friction force on the block is opposite in direction to the displacement , cos θ = -1
➢ Using Uƒ = 0 , Vƒ = 0.20 m/s , and s = 0.70 m
✒ We find ,
➪½mu²ƒ - ½mu²i = Fƒs cos θ
➪0-½ (0.50 kg) (0.20 m/s)² = (Fƒ) (0.70 m) (-1)
➪ Fƒ = 0.014 N
Hope this helped, can i pls have brainliest
Answer:
72
Explanation:
The displacement of an object can be found from the velocity of the object by integrating the expression for the velocity.
In this problem, the velocity of the sport car is given by the expression
In order to find the expression for the position of the car, we integrate this expression. We find:
where C is an arbitrary constant.
Here we want to find the displacement after 3 seconds. The position at t = 0 is
While the position after t = 3 s is
Therefore, the displacement of the car in 3 seconds is
Answer:
Answer B
Explanation:
An increase in resistance makes it harder for the electric current to pass through
Answer:
Explanation:
a )
change in the gravitational potential energy of the bear-Earth system during the slide = mgh
= 45 x 9.8 x 11
= 4851 J
b )
kinetic energy of bear just before hitting the ground
= 1/2 m v²
= .5 x 45 x 5.8²
= 756.9 J
c ) If the average frictional force that acts on the sliding bear be F
negative work done by friction
= F x 11 J
then ,
4851 J - F x 11 = 756.9 J
F x 11 = 4851 J - 756.9 J
= 4094.1 J
F = 4094.1 / 11
= 372.2 N
