Answer:
a)
840 N
b)
10920 J
c)
- 10192 J
d)
4.3 m/s
Explanation:
a)
T = tension force in the cable in upward direction = ?
a = acceleration of the person in upward direction = 0.70 m/s²
m = mass of the person being lifted = 80 kg
Force equation for the motion of person in upward direction is given as
T - mg = ma
T = m (g + a)
T = (80) (9.8 + 0.70)
T = 840 N
b)
d = distance traveled in upward direction = 13 m
= Work done by tension force
Work done by tension force is given as
= T d
= (840) (13)
= 10920 J
c)
d = distance traveled in upward direction = 13 m
= Work done by person's weight
Work done by person's weight is given as
= - mg d
= - (80 x 9.8) (13)
= - 10192 J
d)
= Net force on the person = ma = 80 x 0.70 = 56 N
v₀ = initial speed of the person = 0 m/s
v = final speed
Using work-energy theorem
d = (0.5) m (v² - v₀²)
(56) (13) = (0.5) (80) (v² - 0²)
v = 4.3 m/s
A reference point is a point in geometry or general which is used to determine or refer to another point. In reference to this point, measurements can be done. Like, a reference point in space is used to measure distance or displacement to another point. A reference point in time is used to measure the time interval of an event. A reference in space-time can be used to measure the speed or detect object's motion. Hence, the following points apply:
→A position from which to measure future distance
→a set of standard units for measuring displacement
→a method for determining the speed of an object
→a way to detect an object’s motion
A reference point provides a way/method to infer information about the object.
Momentum = (mass) x (speed)
3300 kg-m/s = (61 kg) x (speed)
Speed = (3300 kg-m/s) / (61 kg)
Speed = 54.1 m/s (about 121 mph)
Answer: The induced electric field will be constant i.e zero
Explanation:
Magnetic field is a region of space where magnetic force can be felt while electric field is a region of space where electric force can be felt. This two field are related because they tend to talk about force of attraction and repulsion. Example is running a current through a thin wire near a magnet, the direction of one of the field will determine the direction of the other.
According to the question, if the magnetic field is decreasing, the electric field will adjust by traveling in opposite direction to the magnetic field just to make the field constant.
Answer:
An acceleration of 5m/s^2 means that the velocity of a body is increasing by 5m/s per second in a certain direction
Explanation:
