1) Size of the image: 2 cm
In order to calculate the size of the image, we can use the following proportion:

where
p = 80 m is the distance of the tree from the pinhole
q = 20 cm = 0.2 m is the distance of the image from the pinhole
= 8 m is the heigth of the object
is the height of the image
By re-arranging the proportion, we find

2) Magnification: 0.0025
The magnification of a camera is given by the ratio between the size of the image and the size of the real object:

so, in this problem we have

Answer:
False
Explanation:
Actually, the converse is true. The mass number would be lower than the sum of the mass of the individual nucleons combined. According to Einstein’s equation of E=MC², this will be due to a phenomenon called mass defect. This ‘anomaly’ is due to the loss of some energy (now the nuclear binding energy) when the nucleons were brought in together to form the nucleus.
Explanation:
Given that,
Angle by the normal to the slip α= 60°
Angle by the slip direction with the tensile axis β= 35°
Shear stress = 6.2 MPa
Applied stress = 12 MPa
We need to calculate the shear stress applied at the slip plane
Using formula of shear stress

Put the value into the formula


Since, the shear stress applied at the slip plane is less than the critical resolved shear stress
So, The crystal will not yield.
Now, We need to calculate the applied stress necessary for the crystal to yield
Using formula of stress

Put the value into the formula


Hence, This is the required solution.
The final velocity of the train after 8.3 s on the incline will be 12.022 m/s.
Answer:
Explanation:
So in this problem, the initial speed of the train is at 25.8 m/s before it comes to incline with constant slope. So the acceleration or the rate of change in velocity while moving on the incline is given as 1.66 m/s². So the final velocity need to be found after a time period of 8.3 s. According to the first equation of motion, v = u +at.
So we know the values for parameters u,a and t. Since, the train slows down on the slope, so the acceleration value will have negative sign with the magnitude of acceleration. Then
v = 25.8 + (-1.66×8.3)
v =12.022 m/s.
So the final velocity of the train after 8.3 s on the incline will be 12.022 m/s.
Answer:
E = 3.8 kJ
Explanation:
Given that,
The mass of the object, m = 10 g = 0.01 kg
The heat of fusion of aluminum is 380 kJ/kg
We need to find the energy required to melt the mass of the aluminium. It can be calculated as follows:
E = mL
So,
E = 0.01 × 380
E = 3.8 kJ
So, the energy required to melt the mass is equal 3.8 kJ.