Answer:

Explanation:
The free body diagram of the block on the slide is shown in the below figure
Since the block is in equilibrium we apply equations of statics to compute the necessary unknown forces
N is the reaction force between the block and the slide
For equilibrium along x-axis we have

Using value of N from equation β in α we get value of force as

Applying values we get

Answer:
The answer is: c. It does not move
Explanation:
Because the gravitational force is characterized by being an internal force within the Earth-particle system, in this case, the object of mass M. And since in this system there is no external force in the system, it can be concluded that the center of mass of the system will not move.
Answer:
37357 sec
or 622 min
or 10.4 hrs
Explanation:
GIVEN DATA:
Lifting weight 80 kg
1 cal = 4184 J
from information given in question we have
one lb fat consist of 3500 calories = 3500 x 4184 J
= 14.644 x 10^6 J
Energy burns in 1 lift = m g h
= 80 x 9.8 x 1 = 784 J
lifts required 
= 18679
from the question,
1 lift in 2 sec.
so, total time = 18679 x 2 = 37357 sec
or 622 min
or 10.4 hrs
Answer:
Total distance does the grasshopper travel before the cars hit is 150 m
Explanation:
Each car moves x=100 m before they collide. Both the cars moving in constant velocity. time taken t by each car is

where x is the distance traveled with velocity v

The insect is moving through this time period with a constant velocity of 15 m/s
The distance traveled by grasshopper is

Answer:
1) in metal object heat transfer through the conduction .In vacuum heat transfer through only radiation .
In only gaseous state or in liquid state the heat transfer through convection hence option D is correct