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Theodore Delacroix
Subject: Science
, asked on 18/1/18
A ball of mass m falls freely from rest. When it has reached a speed v, it strikes a vertical spring.
The spring is compressed by distance y before the ball moves upwards again. Assume that all the energy the ball loses becomes elastic potential energy in the spring what is the average force exerted by the spring during its compression.
Answer
1
Vaibhavi Pawar
Subject: Science
, asked on 17/1/18
A boy weighing 40 kg carries a box weighing 20 kg to the top of building 15 M high in 25 seconds calculate the power
Answer
2
Vaibhavi Pawar
Subject: Science
, asked on 17/1/18
Electricity bill for a particular month reads energy used as 125 units calculate this electrical energy in joules
Answer
1
Vaibhavi Pawar
Subject: Science
, asked on 17/1/18
Find the magnitude of force if the work done by a force is 24.25 in moving it through a distance of 20 CM
Answer
3
Devhuti
Subject: Science
, asked on 17/1/18
name two forms of mechanical energy . define its SI unit of energy .
A man has mass 50 kg jumps from a height of 0.5 m if g = 10m/s
2
, what will be its energy at the highest point
Answer
5
Devhuti
Subject: Science
, asked on 16/1/18
i) Define Kinetic energy. Derive an expression for the kinetic energy of an object.
ii) The power of a moter pump is 5kW. How much water per minute the pump can raise to height of 20m? take g=10 ms
-2
Answer
2
Krithi ♀️
Subject: Science
, asked on 16/1/18
What is e=mc square??(sorry for the words)
Answer
1
Devhuti
Subject: Science
, asked on 16/1/18
Raghu lives in a village and his school 8 km. away from the home. His father suggests buying a motorcycle to go to the school. Raghu opposes the idea for the bicycle instead.
a)if raghu paddles the bicycle with a speed of 8 km/hr and if he wants to reach 10 minutes before the school commences what should be the duration before which he must leave his house
b) justify the stand taken by raghu in your own words.
c) write the energy transformation taking place while raghu rides his bicycle.
Answer
1
Devhuti
Subject: Science
, asked on 16/1/18
a) a truck has much wider tyres why?
b) a child sitting along a swimming pool feels lighter while lowering his legs in water.why?
Answer
2
Devhuti
Subject: Science
, asked on 16/1/18
a body of mass 50 kg runs up a staircase is 15 cm find the power of the boy g=10 m.s
Answer
2
Devhuti
Subject: Science
, asked on 16/1/18
what is meant by 'inertia'? what are the diffrent types of inertia? give two examples in each case
Answer
1
Devhuti
Subject: Science
, asked on 16/1/18
state the law of conservation of energy with the help of an example explain the law of conservation of energy
Answer
1
Devhuti
Subject: Science
, asked on 16/1/18
an electrical geyser of 1.5 kW works for 2 hours. Find the electrical energy units consumed in a day.
Answer
2
Bhavya Biswas
Subject: Science
, asked on 16/1/18
simple defination of potential energy
Answer
4
Bhavya Biswas
Subject: Science
, asked on 16/1/18
Q.
Why we have taken
u
2
as 0 in the derivation of KE given below?
Answer
4
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What are you looking for?
The spring is compressed by distance y before the ball moves upwards again. Assume that all the energy the ball loses becomes elastic potential energy in the spring what is the average force exerted by the spring during its compression.
ii) The power of a moter pump is 5kW. How much water per minute the pump can raise to height of 20m? take g=10 ms-2
a)if raghu paddles the bicycle with a speed of 8 km/hr and if he wants to reach 10 minutes before the school commences what should be the duration before which he must leave his house
b) justify the stand taken by raghu in your own words.
c) write the energy transformation taking place while raghu rides his bicycle.
b) a child sitting along a swimming pool feels lighter while lowering his legs in water.why?
Q. Why we have taken as 0 in the derivation of KE given below?