Consider the motion of the car before brakes are applied:
v₀ = maximum initial velocity of the car before the brakes are applied
t = reaction time = 0.50 s
x₀ = distance traveled by the car before brakes are applied
since car moves at constant speed before brakes are applied
Using the equation
x₀ = v₀ t
x₀ = v₀ (0.50)
Consider the motion after brakes are applied :
v₀ = initial velocity of the car before the brakes are applied
a = acceleration = - 10 m/s²
v = final velocity of the car after it comes to stop = 0 m/s
x = stopping distance = initial distance - distance traveled before applying the brakes = 38 - x₀ = 38 - v₀ (0.50)
Using the equation
v² = v²₀ + 2 a x
inserting the values
0² = v²₀ + 2 (- 10) (38 - v₀ (0.50))
v²₀ = 20 (38 - v₀ (0.50))
v₀ = 23 m/s
Question:
Diffusion is the movement of particles from high to low concentration. True or False
Answer:
True.
Explanation:
Diffusion is a process that allows the movement of substance or particles in and out of cells through a semipermeable membrane.
Diffusion is a process that allows the spread or movement of particles from the region of higher concentration to a region of lower concentration through a semipermeable membrane.
Diffusion only occurs in gases and solution but not in solids, it also occurs only where particles can move freely.
Note: When particles move from the region of higher concentration to a lower concentration, it gives room for even, uniform and random distribution of particles.
Answer:
Dry-strength additives, or dry-strengthening agents, are chemicals that improve paper strength normal conditions. These improve the paper's compression strength, bursting strength, tensile breaking strength, and delamination resistance. Typical chemicals used include cationic starch and polyacrylamide derivatives.
Answer:
2682
Explanation:
Work done is given by :
Work = Force x distance
= mg x d
So, work done in lifting the box of 23 kg up to my waist of 1 m high is :
W = mg x d
= 23 x 9.18 x 1
= 211.14
Now work done carrying the box horizontally 6 meters across the room is
W = mg x d
= 23 x 9.18 x 6
= 1266.84
Work done in placing the box on the shelf that is 5.7 m above the ground is
W = mg x d
= 23 x 9.18 x 5.7
= 1203.49
So the total work done is = 211.14 + 1266.84 + 1203.49
= 2681.47
= 2682 (rounding off)
