Answer:
The weight of the block on the moon is 15 kg.
Explanation:
It is given that,
The acceleration of the block, a = 7.5 m/s²
Force applied to the box, F = 70 N
The mass of the block will be, 

m = 9.34 kg
The block and table are set up on the moon. The acceleration due to gravity at the surface of the moon is 1.62 m/s². The mass of the object remains the same. It weight W is given by :


W = 15.13 N
or
W = 15 N
So, the weight of the block on the moon is 15 kg. Hence, this is the required solution.
Answer:
T=502.5N
Ax=171.8N
Explanation:
The computation of the tension T in the rope and the forces exerted by the pin at A is shown below:
vertical forces sum = Ay + Tsin20 + T - 245 - 883 = 0
Now
horizontal forces sum = Ax - Tcos70
Now Moment about B
-Ay × 4.8 + 245 × 2.4 + 883 × 1.8=0
Ay=453.6N
Now substitute in sum of vertical forces T=502.5N
Ax=171.8N
Answer:

Explanation:
We need to find the energy for an electron to jump from n = 1 to n = 4.
The energy in transition from 1 state to another is given by :

The difference in energy for n = 1 to n = 4 is:

So, the required energy is equal to
.
Answer: 40.650406504065 or 40 minutes and 39 seconds.
Explanation:
1 k = 1000m
race = 10000m
runner time = 10000 / 4.1
runner time = 2439.0243902439024 seconds
runner time = 2439.0243902439024/60 = 40.650406504065 or 40 minutes and 39 seconds.