Answer:
Explanation:
We shall find first the velocity of ball at the time when string breaks. Let it be v . During its fall on the ground , 1.02 m below, we use the formula
h = 1/2 gt² where t is time of fall .
1.02 = 1/2 x 9.8 x t²
t²= .2081
t = .456
During this time it travels horizontally at distance of 2.5 m with uniform velocity of v
v x .456 = 2.5
v = 5.48 m /s
centripetal acceleration
= v² / r where r is radius of the circular path
= 5.48² / .478
= 62.82 m /s²
Answer:
Calculate the total distance travelled by the object - its motion is represented by the velocity-time graph below.
Here, the distance travelled can be found by calculating the total area of the shaded sections below the line.
½ × base × height.
½ × 4 × 8 = 16 m 2
(10 – 4) × 8 = 48 m 2
Explanation:
Answer:
A _commutator_ is used in a motor to switch the direction of the magnetic field created by the current.
The rotating part of a motor that holds the electromagnets is called the __armature___.
Electric current passes through the _brushes_ and into the electromagnets in an electric motor.
A motor turns _electrical_ energy into _mechanical_ energy.
Explanation:
A commutator, which is a split ring rotary switching device, reverses the direction of the current between the external circuit and the rotor. Reversing the current reverses the magnetic field.
The armature comprises the rotating part of the motor and the electromagnets
A brush is the electrical contact for conducting current through the moving and stationary parts of an electric motor
An electric motor turns electrical energy into mechanical energy.
The answer is <span>C. 49 m/s
The kinetic equation is:
v2 = v1 + a * t
v1 - initial velocity
v2 - final velocity
a - gravitational acceleration
t - time
We know:
v2 = ?
v1 = 0 (in free fall
a = 9.8 m/s
t = 5
</span>v2 = v1 + a * t
v2 = 0 + 9.8 * 5
v2 = 0 + 49
v2 = 49 m/s
