Answer:
At a deceleration of 60g, or 60 times the acceleration due to gravity a person will travel a distance of 0.38 m before coing to a complete stop
Explanation:
The maximum acceleration of the airbag = 60 g, and the duration of the acceleration = 36 ms or 36/1000 s or 0.036 s
To find out how far (in meters) does a person travel in coming to a complete stop in 36 ms at a constant acceleration of 60g
we write out the equation of motion thus.
S = ut + 0.5at²
wgere
S = distance to come to complete stop
u = final velocoty = 0 m/s
a = acceleration = 60g = 60 × 9.81
t = time = 36 ms
as can be seen, the above equation calls up the given variable as a function of the required variable thus
S = 0×0.036 + 0.5×60×9.81×0.036² = 0.38 m
At 60g, a person will travel a distance of 0.38 m before coing to a complete stop
Answer:
Explanation:
Given that,
Mass of counterweight m= 4kg
Radius of spool cylinder
R = 8cm = 0.08m
Mass of spool
M = 2kg
The system about the axle of the pulley is under the torque applied by the cord. At rest, the tension in the cord is balanced by the counterweight T = mg. If we choose the rotation axle towards a certain ~z, we should have:
Then we have,
τ(net) = R~ × T~
τ(net) = R~•i × mg•j
τ(net) = Rmg• k
τ(net) = 0.08 ×4 × 9.81
τ(net) = 3.139 Nm •k
The magnitude of the net torque is 3.139Nm
b. Taking into account rotation of the pulley and translation of the counterweight, the total angular momentum of the system is:
L~ = R~ × m~v + I~ω
L = mRv + MR v
L = (m + M)Rv
L = (4 + 2) × 0.08
L = 0.48 Kg.m
C. τ =dL/dt
mgR = (M + m)R dv/ dt
mgR = (M + m)R • a
a =mg/(m + M)
a =(4 × 9.81)/(4+2)
a = 6.54 m/s
False. Since the forces are pulling in equal and opposite directions, the net force is 0.
Answer:
A concave mirror has a radius of curvature of 20 cm. What is it's focal length? If an object is placed 15 cm in front of it, where would the image be formed? What is it's magnification?
The focal length is of 10 cm, object distance is 30 cm and magnification is -2.
Explanation:
Given:
A concave mirror:
Radius of curvature of the mirror, as C = 20 cm
Object distance in-front of the mirror = 15 cm
a.
Focal length:
Focal length is half of the radius of curvature.
Focal length of the mirror =
= 10 cm
According to the sign convention we will put the mirror on (0,0) point, of the Cartesian coordinate open towards the negative x-axis.
Object and the focal length are also on the negative x-axis where focal length and image distance will be negative numerically.
b.
We have to find the object distance:
Formula to be use:
⇒ 
⇒ Plugging the values.
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
Image will be formed towards negative x-axis 30 cm away from the pole.
c.
Magnification (m) is the negative ratio of mage distance and object distance:
⇒ 
⇒ 
⇒ 
The focal length of the concave mirror, is of 10 cm, object distance is 30 cm and magnification is -2.