Answer:
Explanation:
Given
mass of object hanging from crane is 
mass is speeding up with 
If T is the Tension in the cable then






Explanation:
Given that,
A person walks 9.0 km directly east and then turns left and heads directly north for 12.0 km.
We need to find his displacement from the starting position.
We know that,
Displacement = shortest path covered

For direction,

Hence, this is the required solution.
Answer:
17.5 N
Explanation:
<h2>Given :</h2>
- Mass (m) = 2.5 kg
- Acceleration (a) = 7.0 m/s²
<h2>To calculate :</h2>
<h2>Calculation :</h2>
<h3>• F = ma</h3>
→ F = (2.5 × 7.0) N
→ F = 25/10 × 7 N
→ F = 5/2 × 7 N
→ F = (5 × 7)/2 N
→ F = 35/2 N
→ <u>F</u><u> </u><u>=</u><u> </u><u>1</u><u>7</u><u>.</u><u>5</u><u> </u><u>N</u><u> </u><u>towards</u><u> </u><u>left</u>
Hence, 17.5 N of net force must act on the book to make it accelerate to the left.
Answer:
the photons (quanta of light) collide with the electrons, these electrons have to overcome the threshold energy that is the energy of union with the metal, and the energy that remains is converted to kinetic energy.
K = E - Ф
Explanation:
The photoelectric effect is the emission of electrons from the surface of a metal.
This was correctly explained by Einstein, in his explanation the energy of the photons (quanta of light) collide with the electrons, these electrons have to overcome the threshold energy that is the energy of union with the metal, and the energy that remains is converted to kinetic energy.
E = hf
E = K + Ф
K = E - Ф
The energy of the photons is given by the Planck relation E = hf and according to Einstein the number of joints must be added
E = n hf
Therefore, depending on the value of this energy, the emitted electrons can have energy from zero onwards.
Answer:
1.97 seconds
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.8 m/s²

Solving the above equation we get

So, the time the package was in the air is 1.97 seconds