Physics Answers

A 54g copper calorimeter contains 80cm3 at 20∘C. A very cold 110g copper cylindrical sample is dropped into the water causing the water to partially freeze, with 5cm3 being converted to ice. The final temperature of the system is 0∘C. What is the initial temperature in Kelvins of the cylindrical sample?

A 54g copper calorimeter contains 80cm3 at 20∘C. A very cold 110g copper cylindrical sample is dropped into the water causing the water to partially freeze, with 5cm3 being converted to ice. The final temperature of the system is 0∘C. What is the initial temperature in Kelvins of the cylindrical sample?

Consider a vector described by the following components:x-component= +5.5 my-component-8.2mWhat is the magnitude of the vector and its direction relative to the x-axis?

Three identical coils, each of resistance 15 Ω and inductance 42 mH are
connected (a) in star and (b) in delta to a 415 V, 50 Hz, 3-phase supply.
Determine the total power dissipated in each case.

Three identical coils, each of resistance 15 Ω and inductance 42 mH are
connected (a) in star and (b) in delta to a 415 V, 50 Hz, 3-phase supply.
Determine the total power dissipated in each case.

The rectilinear motion of a body with a mass of 2 kg is given by the law s= 2t +t^2.
What is the force acting on the body?

Two vectors A=5i-6j+4k and B=-3i+8j-2k
Find :
a- (A . B)
b- (AxB) and its magnitude
c- (A - 2B) and its magnitude
d- The angle between vectors A and B

A toy bird of mass 2kg is
being hung from the ceiling with the help of a 0.1m rope. A bullet of mass 0.01kg hits the bird horizontally and
sticks to it. If the bird afterwards, at its highest vertical displacement touches the ceiling anyway, what was the
speed of the bullet?

3. A car moving with constant acceleration covers the distance between two points 60 m apart in 6 s. Its velocity as it passes the second point is 15 m/s.
a) What is its velocity at the first point?
b) What is the acceleration?

7. An automobile and a truck start from rest at the same instant, with the automobile initially at some distance behind the truck. The truck has a constant acceleration of 2 m/s2 and the automobile an acceleration of 3 m/s2. The automobile overtakes the truck after the truck has moved 75 m.
a) How long does it take the automobile to overtake the truck?
b) How far was the car behind the truck initially?
c) What is the velocity of each when they are abreast?