Answer
given,
position of particle
x(t)= A t + B t²
A = -3.5 m/s
B = 3.9 m/s²
t = 3 s
a) x(t)= -3.5 t + 3.9 t²
velocity of the particle is equal to the differentiation of position w.r.t. time.

------(1)
velocity of the particle at t = 3 s
v = -3.5 + 7.8 x 3
v = 19.9 m/s
b) velocity of the particle at origin
time at which particle is at origin
x(t)= -3.5 t + 3.9 t²
0 = t (-3.5 + 3.9 t )
t = 0, 
t = 0 , 0.897 s
speed of the particle at t = 0.897 s
from equation (1)
v = -3.9 + 7.8 t
v = -3.9 + 7.8 x 0.897
v = 3.1 m/s
Answers that apply include
- Energy is transferred through vibrating particles
- An ocean wave moving through water is an example of a mechanical wave
- A longitudinal wave is a type of mechanical wave.
- A transverse wave is a type of mechanical wave
Mechanical waves can't pass through vacuum like electromagnetic waves because t depends on the transfer of energy between particles of matter (matter that has inertia and elasticity). This energy propagates in the same direction as the wave. Another example of mechanical energy is sound. In addition to longitudinal and transverse waves, another type of mechanical wave is surface waves.
Answer: 1,500m/s
Explanation:
Relationship existing between velocity of a wave (v), wavelength(¶) and frequency(f) is
v = f¶... (1)
Since Frequency (f) is the reciprocal of the period (T);
Frequency = 1/Period i.e F = 1/T... (2)
Substituting equation 2 into 1 we have;
v = 1/T × ¶
v = ¶/T
Given wavelength ¶ = 9m
Period T = 0.006s
v = 9/0.006
v = 1,500m/s
The velocity of the wave will be 1,500m/s
Answer:
The correct answer is = 1.6
Explanation:
Density of water = 1000kg/m³ = d₁
Mass of brick = 4kg = m
Density of brick = 2.5 g/cm³ = 2.5 × 1000 =2500 kg/m³ = d₂
Volume of brick = m/d₂ = 4/2500 =16/10000 = 0.0016 L = v
Buoyant Force = v × d₁ × g (g= acceleration due to gravity =9.8m/s²)
= 0.0016 × 1000 × 9.8 = 15.68 Newtons
By the Archimedes' Principle, the buoyant force is equal to the weight of the liquid displaced by an object.
Weight of the water displaced=Buoyant Force
=Mass of water displaced × g,
as weight = mass × acceleration due to gravity
15.68= mass of brick × 9.8
15.68/9.8 =Mass of water displaced
1.6 kg = Mass of water displaced