1. a curling stone has a mass of 45 kg. it has an initial speed of 1.1 m/s and travels 45 m to hit the target and come to a stop. determine the coefficient of kinetic friction between the ice and the stone.

0.0013

Explanation:

m = 45kg

s = 45m

u = 1.1m/s

v = 0

a = ?

g = 10m/s

using equation of motion to find the acceleration of the curling stone.

v² = u² + 2as

0² = 1.1² + 2a × 45

a = -0.013m/s (deceleration)

Fk = #R

# = a/g = 0.013/10 = 0.0013

NB: check the initial velocity in the question, i think its too small

what is the question because that is not a question.

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.