Answer:
Explanation:
a ) x ( t ) = t³ / 3 - t² + t
v = dx / dt = 3 t² / 3 - 2 t + 1 = t² - 2 t + 1
b ) lizard is at rest , v( t ) = 0
t² - 2 t + 1 = 0
( t - 1 )² = 0
t = 1
c )
velocity is positive when
t² - 2 t + 1 > 0
( t - 1 ) ² > 0
Here we see that LHS is a square so it is always positive whatever be the value of t
So velocity is always positive or lizard is always moving in positive x direction .
d ) It never moves in negative x direction .
e )
a ( t ) = dv / dt = 2t - 2
t = 1
so it has zero acceleration at t = 0 .
Answer:
3.0 x 10¹ Nm
Explanation:
Torque = F x r
Where F is force applied and r is perpendicular distance from pivot point . r
is also called lever arm
Here F = 15 N and r = 2.0 m
Torque
= 15 N X 2.0 m
= 3.0 10¹ Nm.
Answer:
All of the above
Explanation:
Sound waves are mechanical waves consisting of the oscillations of the particles in a medium. They are longitudinal waves, which means that the vibrations of the particles occur in a direction parallel to the direction of propagation of the wave.
This type of wave consists of alternating regions where:
- the density of the particles is higher: these regions are called compressions, and they correspond to high pressure regions
- the density of the particles is lower: these regions are called rarefactions, and they correspond to low pressure regions
Vf=V1+at
0=31+a(7)
-31/7=a
a=-4.43m/s^2
Hope this helps.
