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: nuclear energy
Explanation: nuclear energy
The concave lens is a diverging lens, because it causes the light rays to bend away (diverge) from its axis. In this case, the lens has been shaped so that all light rays entering it parallel to its axis appear to originate from the same point, F, defined to be the focal point of a diverging lens.
Coupla things wrong with this question, Sam.
Let's clean those up first, and then we'll work on the answer.
-- The car is NOT moving with uniform velocity.
'Velocity' includes both speed and direction. If either of these
changes, it's a change of velocity.
On a circular track, the car's direction is CONSTANTLY changing,
so its velocity is too.
The thing that's uniform is its speed, not its velocity.
-- A 'neutron' is a subatomic particle found in the nucleus of most
atoms. It's not a unit of force. The unit of force is the 'Newton'.
_______________________
OK. A centripetal force of 6,000 newtons keeps 1,200 kg of mass
moving in a circle at 20 m/s.
The formula:
Centripetal force = (mass) (speed)² / (radius)
Multiply each side
by 'radius': (centripetal force) x (radius) = (mass) x (speed)²
Divide each side by
'centripetal force': Radius = (mass) x (speed)² / (centripetal force)
Write in the numbers
that we know: Radius = (1200 kg) (20 m/s)² / (6000 Newtons)
= (1200 kg) (400 m²/s²) / (6000 Newtons)
= (480,000 kg-m²/s²) / (6000 kg-m/s²)
= (480,000 / 6000) meters
= 80 meters .
