Answer:
speed v = 0.148 m / s
velocity v = 0
Explanation:
In this exercise we must be careful that the speed is a scalar and the speed is a vector, let's start by looking for the speed
v = Δx /Δt
the distance traveled is x = 2d and the time taken is
t = 7h 30 min
let's reduce to seconds
t = 7 h 3600s / 1h + 30 min 60s / 1min = 27000 s
so the speed is
v = 2d / 27000
to finish the calculation suppose a distance traveled d = 2000 m
v = 2 2000/27000
v = 0.148 m / s
this is the raides which is the speed module
Velocity is a vector,
v = Dx / Dt
in this case the displacement is
Dx = d -d
Dx = 0
the total displacement is zero since it returns to the starting point, consequently the velocity is zero
v = 0
bold is a vector
Momentum = 0.5 * 4 = 2
to conclude the man’s velocity after he throws the piece of equipment, divide
this number by the man’s mass.
v = 2/90
This is about 0.0222 m/s. To know if he can move 6 meters at velocity in
4minutes, use the following equation.
d = v * t, t = 4 * 60 = 240 s
d = 2/90 * 240 = 5⅓ meters.
This is ⅔ of a meter from the spaceship. To know the velocity that he must have
to move 6 meter, use the same equation.
6 = v * 240
v = 6/240
This is about 0.00416 m/s.
His final momentum = 90 * 6/240 = 2.25
To know the velocity of the package, divide this number by the mass of the
package.
v = 2.25/0.5 = 4.5 m/s
Give u = start velocity
v = end velocity
v = u + at
50 = 400 + a*30
30a = -350
a = -116.67 m/
**Why the accecleration is negative number**
Because displacement, velocity, and acceleration are VECTOR QUANTITIES.
Vector Quantity must have direction.