Answer:
Explanation:
The hippopotamus hearing threshold is 100dB
β = 100 dB
The threshold of human hearing is Io = 1 × 10^-12 W/m²
The sound intensity level is given as
β = 10•Log(I / Io)
100 = 10•Log(I / Io)
Divided Both sides by 10
100 / 10 = Log(I / Io)
10 = Log(I / Io)
Take inverse Logarithm ( antilog) of both sides
10^10 = 10^[Log(I / Io)]
10^10 = I / Io
Then,
I = 10^10 × Io
I = 10^10 × 1 × 10^-12
I = 1 × 10^-2 W/m²
I = 0.01 W/m²
The sound intensity is 0.01 W/m²
Water was confirmed to be on the sunlit surface of the Moon
For #5 It's helpful to draw a free body diagram so you know which way the forces are acting on the block.
the weight mg is acting downwards, and you need to find the vertical and horizontal components of mg using sin and cosine. so do 15x9.8xsin40 which is the force. Assuming no friction, this is the only force acting on the block, as the forces on the vertical plane cancel out i.e the normal force and weight of the block.
after, just do F=ma And since you know F and m, solve for a.
Centripital acceleration. When an object moves in a circle, centripital acceleration acts to accelerate the object towards the center of that circle
Weight of the barbell W = 200 Ndistance of the joint is r = 40 cm = 0.4 mtorque created by the weight at the joint is τ = F*r = 200 N*0.4 m = 80 N.mat equilibrium condition , Στ = force*distance - 80 N.m = 0 F'*0.4 - 80 N.m = 0 F'*0.4 = 80 force F' = 200 N
